HighCVE-2026-13676

fast-uri vulnerable to host confusion via failed IDN canonicalization (CVE-2026-13676)

Published 29.06.2026Last modified 11.09.2026Sources: Red Hat, BSI, OSV, CVE.org

What is affected, what to do

A flaw was found in fast-uri. This vulnerability occurs because fast-uri fails to properly convert Unicode (Internationalized Domain Name - IDN) hostnames for HTTP-family URLs.

Update Fast-uri to version 4.0.1, Fast-uri to version 3.1.3.

Affected: Fast-uri lt 4.0.0..4.0.1
Fast-uri lt 2.3.1..3.1.3
Fixed in: Fast-uri 4.0.1
Fast-uri 3.1.3

Not sure whether and how you are affected? Ask a question about this vulnerability

Metrics

7.5

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: NVD, CVSS v3

7.5

CVSS v3

Severity High on the scale from 0 to 10.

Source: Red Hat, BSI, OSV, CVE.org

0.7 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 52.7

Show all metrics

Severity: High
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 79.55 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: no public PoC known
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 7.5 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 7.5
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 0.7 %; Low — model estimates < 1% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 52.7; High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 29.06.2026
CWE CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect. Read in glossary: CWE-436

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

A flaw was found in fast-uri. This vulnerability occurs because fast-uri fails to properly convert Unicode (Internationalized Domain Name - IDN) hostnames for HTTP-family URLs. This can lead to a situation where security policies, such as denylists or redirect validations, are bypassed when applications use fast-uri to enforce these policies before passing the URL to another parser. A remote attacker could exploit this to circumvent security controls and potentially access unauthorized resources or perform malicious redirects.

Source: redhat_csaf, BSI WID Portal, BSI CSAF, OSV (Open Source Vulnerabilities), cvelistv5, NVD (NIST)

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

Affected products
		Affected versions	Fixed in
fast-uri	fast-uri	`4.0.0 – < 4.0.1` `2.3.1 – < 3.1.3`	`4.0.1` `3.1.3`
openjsf	fast-uri	`2.3.1 – < 3.1.3` `4.0.0 – < 4.0.1`	`3.1.3` `4.0.1`
IBM	App Connect Enterprise	`< 12.0.12.28` `< 13.0.8.1`	`12.0.12.28` `13.0.8.1`
Red Hat	Ansible Automation Platform	`2.2`	—
Red Hat	OpenShift	`Container Platform 4.22.5`	—

Vendors and products

Weakness classes (CWE)

CWE-436Interpretation Conflict
Class
Product A handles inputs or steps differently than Product B, which causes A to perform incorrect actions based on its perception of B's state.
Entry at MITRE CWE-436

References & sources

github.comfastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6web
NVD (NIST)vuln/detail/CVE-2026-13676advisory
github.comfastify/fast-uri/pull/188web
github.comfastify/fast-uri/commit/2a6d357a18a68e6d812824379fd3388a1ae50d05web
github.comfastify/fast-uri/commit/21ea1f9d70495c931f55dff893a8fa38f4f2e6bdweb
github.comfastify/fast-uri/commit/01db48010f594b98f7b323be18b393791c66ed1dweb
security.access.redhat.comdata/csaf/v2/vex/2026/cve-2026-13676.jsonweb, x_sadp-csaf-vex
github.comfastify/fast-uri/releases/tag/v4.0.1web
github.comfastify/fast-uri/releases/tag/v3.1.3web
github.comfastify/fast-uri/releases/tag/v2.4.2web
github.comfastify/fast-uripackage
cna.openjsf.orgsecurity-advisories.htmlweb
bugzilla.redhat.comRHBZ#2494197web, Issue tracking, x_refsource_REDHAT
access.redhat.comsecurity/cve/CVE-2026-13676web, Vulnerability database, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:48126web, Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:48124web, Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:44268web, Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:44239web, Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:43038web, Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:42815web, Vendor advisory, x_refsource_REDHAT

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

11.09.2026Record modifiedRed Hat ADP

New references:

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/13xxx/CVE-2026-13676.json">CVE-2026-13676</a>
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:66488
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:66545

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

10.09.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/13xxx/CVE-2026-13676.json">CVE-2026-13676</a>

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

09.09.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/13xxx/CVE-2026-13676.json">CVE-2026-13676</a>

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

07.09.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/13xxx/CVE-2026-13676.json">CVE-2026-13676</a>

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

31.08.2026Record modifiedRed Hat ADP
New references:
- https://access.redhat.com/errata/RHSA-2026:61314
Show the original change
Individual changes of this event as published by NVD
Type Action Before After
Reference added
—
https://access.redhat.com/errata/RHSA-2026:61314
Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:61314

Show 21 older changes

28.08.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:60520

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/13xxx/CVE-2026-13676.json">CVE-2026-13676</a>
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:60520

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

25.08.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Enterprise Linux 10, multicluster engine for Kubernetes 2.11, Red Hat Advanced Cluster Management for Kubernetes 2.16 (+155)	Red Hat Enterprise Linux 10, multicluster engine for Kubernetes 2.11.0, Red Hat Advanced Cluster Management for Kubernetes 2.16 (+155)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

24.08.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Enterprise Linux 10, multicluster engine for Kubernetes 2.11, Red Hat Advanced Cluster Management for Kubernetes 2.16 (+155)	Red Hat Enterprise Linux 10, multicluster engine for Kubernetes 2.11, Red Hat Advanced Cluster Management for Kubernetes 2.16 (+155)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

21.08.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:57590

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:57590
Affected versions (publisher)	changed	Red Hat Advanced Cluster Management for Kubernetes 2.16, Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6 (+155)	Red Hat Enterprise Linux 10, multicluster engine for Kubernetes 2.11, Red Hat Advanced Cluster Management for Kubernetes 2.16 (+155)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

20.08.2026Record modifiedRed Hat ADP

New references:

Show 4 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:57013
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:57191
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:57194
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+133)	Red Hat Advanced Cluster Management for Kubernetes 2.16, Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6 (+155)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

19.08.2026Record modifiedRed Hat ADP

New references:

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:56366
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:56431
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+98)	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+133)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

18.08.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+98)	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+98)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

10.08.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+97)	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+97)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

06.08.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:47728

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:47728
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+94)	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+95)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

05.08.2026Record modifiedRed Hat ADP

New references:

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:50340
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:50479
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.10, Red Hat Developer Hub 1.10 (+93)	Red Hat Ansible Automation Platform 2.2, Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7 (+94)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

04.08.2026Record modifiedRed Hat ADP
New references:
- https://access.redhat.com/errata/RHSA-2026:49642
Show the original change
Individual changes of this event as published by NVD
Type Action Before After
Reference added
—
https://access.redhat.com/errata/RHSA-2026:49642
Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:49642

03.08.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.10, Red Hat Developer Hub 1.10 (+93)	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.10, Red Hat Developer Hub 1.10 (+93)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

30.07.2026Record modifiedRed Hat ADP

New references:

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:48124
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:48126
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+88)	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.10, Red Hat Developer Hub 1.10 (+93)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

28.07.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:44239

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:44239
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+87)	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+87)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

27.07.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+87)	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+87)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

23.07.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:40765

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:40765
Affected versions (publisher)	changed	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+86)	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+87)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

22.07.2026Record modifiedRed Hat ADP

New references:

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:42815
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:43038
Affected versions (publisher)	changed	Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1 (+86)	Red Hat Ansible Automation Platform 2.2, Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1 (+86)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

21.07.2026Record modifiedRed Hat ADP

New references:

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:41928
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:41929
Affected versions (publisher)	changed	Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1 (+86)	Red Hat Developer Hub 1.9, Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1 (+86)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

20.07.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1 (+86)	Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1, Red Hat Edge Manager 1.1 (+86)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

02.07.2026Initial analysis by NVDNVD

Newly listed as affected:

Openjsf OpenJS Foundation fast-uri (2.3.1 – before 3.1.3; 4.0.0 – before 4.0.1)

New references:

and 1 more reference

Show 6 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Product configuration	added	—	OR cpe:2.3:a:openjsf:fast-uri::::::node.js:: versions from (including) 2.3.1 up to (excluding) 3.1.3 cpe:2.3:a:openjsf:fast-uri::::::node.js:: versions from (including) 4.0.0 up to (excluding) 4.0.1
Reference type	added	—	openjs: https://cna.openjsf.org/security-advisories.html Types: Vendor Advisory
Reference type	added	—	openjs: https://github.com/fastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6 Types: Patch, Vendor Advisory
Reference type	added	—	redhat-SADP: https://access.redhat.com/security/cve/CVE-2026-13676 Types: Third Party Advisory
Reference type	added	—	redhat-SADP: https://bugzilla.redhat.com/show_bug.cgi?id=2494197 Types: Third Party Advisory
Reference type	added	—	redhat-SADP: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-13676.json Types: Third Party Advisory

Source identifier: nvd@nist.gov

29.06.2026ReceivedOpenJS Foundation

CVSS V3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Weakness type: CWE-436

Description added or changed

New references:

Show 6 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	fast-uri
Description	added	—	fast-uri versions 2.3.1 through 3.1.2 and 4.0.0 fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still return values that differ from a WHATWG-compatible URL parser. Applications that use fast-uri to enforce host-based policy (denylists, loopback filtering, redirect validation, outbound proxy routing) before passing the same URL to Node's URL or fetch can be bypassed when the two implementations resolve the same input to different hosts. Patches: upgrade to fast-uri 3.1.3 for the 3.x line or 4.0.1 for the 4.x line. Workarounds: enforce host policy using the same URL parser used for the actual request, or reject non-ASCII hosts before policy checks.
CVSS	added	—	AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness type (CWE)	added	—	CWE-436
Reference	added	—	https://cna.openjsf.org/security-advisories.html
Reference	added	—	https://github.com/fastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6

Source identifier: ce714d77-add3-4f53-aff5-83d477b104bb

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