HighCVE-2026-73276

inets, httpd: HTTP Request Smuggling via Whitespace-Before-Colon Header Dropping i (CVE-2026-73276)

Published 01.09.2026Last modified 08.09.2026Sources: Debian, Ubuntu, BSI, CVE.org, OSV, Msrc Update Guide

What is affected, what to do

Gracefulness code ignored cases that should be rejected, resulting in possible HTTP Request Smuggling opportunities. This issue affects OTP from OTP 22.2 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 7.1.2 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2.

Update Erlang OTP to version 27.3.4.17, Erlang OTP to version 28.5.0.6, Erlang OTP to version 29.0.6.

Affected: Erlang OTP lt 22.2..27.3.4.17
Erlang OTP lt 28.0..28.5.0.6
Erlang OTP lt 29.0..29.0.6
Erlang OTP lt 7.1.2..9.3.2.7
Erlang OTP lt 9.4..9.6.2.3
Erlang OTP lt 9.7..9.7.2
Fixed in: Erlang OTP 27.3.4.17
Erlang OTP 28.5.0.6
Erlang OTP 29.0.6
Erlang OTP 9.3.2.7
Erlang OTP 9.6.2.3
Erlang OTP 9.7.2

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Metrics

8.3

Priority

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

Source: Vendor (CNA), CVSS v4

8.3

CVSS v4

Severity High on the scale from 0 to 10.

Source: Debian, Ubuntu, BSI, CVE.org, OSV, Msrc Update Guide

0.6 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 47.4

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: 84.70 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: 8.3 Methodology
CVSS v4 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: 8.3
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: 0.6 %; 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: 47.4; 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: 01.09.2026
CISA assessment (SSVC): Exploitation: none known · not automatable · Technical impact: partial; Source: CISA Vulnrichment, as of 1 September 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-444

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

Source: Debian Security Advisories, Ubuntu Security Notices, BSI WID Portal, BSI CSAF, cvelistv5, NVD (NIST), OSV (Open Source Vulnerabilities), Microsoft Security Update Guide

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
Erlang	OTP	`28.0 – < 28.5.0.6` `7.1.2 – < 9.3.2.7` `9.4 – < 9.6.2.3` `29.0 – < 29.0.6` `9.7 – < 9.7.2` `22.2 – < 27.3.4.17`	`28.5.0.6` `9.3.2.7` `9.6.2.3` `29.0.6` `9.7.2` `27.3.4.17`
Open Source	Erlang/OTP	`< 28.5.0.6` `< 27.3.4.17` `< 29.0.6`	`28.5.0.6` `27.3.4.17` `29.0.6`

Vendors and products

Affected operating systems

Affected operating systems

Linux	debian	erlang	`trixie`
Linux	ubuntu	erlang	`bionic`
Linux	ubuntu	erlang	`focal`
Linux	ubuntu	erlang	`jammy`
Linux	ubuntu	erlang	`noble`
Linux	ubuntu	erlang	`resolute`
Linux	ubuntu	erlang	`trusty`
Linux	ubuntu	erlang	`xenial`

Weakness classes (CWE)

CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Base
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
Entry at MITRE CWE-444

References & sources

github.comerlang/otp/security/advisories/GHSA-6v7q-jwgh-cx8pVendor advisory
cna.erlef.orgcves/CVE-2026-73276.htmlrelated
OSV (Open Source Vulnerabilities)vulnerability/EEF-CVE-2026-73276related
github.comerlang/otp/commit/60add5a19e2154560fdff3fe92dba14a68bbd683Patch
github.comerlang/otp/commit/6cd995e34d3bb3d36dd278dded2d62c25e71820cPatch
github.comerlang/otp/commit/c285240c6e4b93960c5dc4f17ba04e6fdfb27a0fPatch

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).

08.09.2026Record modifiedEEF

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/2026/73xxx/CVE-2026-73276.json">CVE-2026-73276</a>

Source identifier: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

01.09.2026Record modifiedCISA ADP

CISA assessment (SSVC): exploitation: none known, automatable: no

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
SSVC assessment	added	—	{"id":"CVE-2026-73276","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-09-01T15:55:23.919951Z"}

Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

01.09.2026ReceivedEEF

CVSS V4.0: AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N

Weakness type: CWE-444

Description added or changed

New references:

and 2 more references

Show 10 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Description	added	—	Gracefulness code ignored cases that should be rejected, resulting in possible HTTP Request Smuggling opportunities. This issue affects OTP from OTP 22.2 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 7.1.2 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2.
CVSS	added	—	AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness type (CWE)	added	—	CWE-444
Affected versions (publisher)	added	—	New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/73xxx/CVE-2026-73276.json">CVE-2026-73276</a>
Reference	added	—	https://cna.erlef.org/cves/CVE-2026-73276.html
Reference	added	—	https://github.com/erlang/otp/commit/60add5a19e2154560fdff3fe92dba14a68bbd683
Reference	added	—	https://github.com/erlang/otp/commit/6cd995e34d3bb3d36dd278dded2d62c25e71820c
Reference	added	—	https://github.com/erlang/otp/commit/c285240c6e4b93960c5dc4f17ba04e6fdfb27a0f
Reference	added	—	https://github.com/erlang/otp/security/advisories/GHSA-6v7q-jwgh-cx8p
Reference	added	—	https://osv.dev/vulnerability/EEF-CVE-2026-73276

Source identifier: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

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