Angular: Denial of Service via RouterLink Query Parameter Retention in Server-Side Rendering (SSR) (CVE-2026-111751)
Published Last modified Sources: BSI, CVE.org, OSV, Hersteller
What is affected, what to do
Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. From 21.2.0 until 21.2.25 and 22.2.1, RouterLink directives rendered during Node.js server-side rendering retain computed UrlTree instances for the lifetime of each request.
Update Angular to version 21.2.25, @angular/router to version 21.2.25.
- Affected
- Angular
gte 21.2.0, < 21.2.25..*
- Angular
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Metrics
8.2
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: Vendor (CNA), CVSS v4
8.2
CVSS v4
Severity High on the scale from 0 to 10.
Source: BSI, CVE.org, OSV, Hersteller
0.7 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 51.7
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- 92.37 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- 8.2 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- 8.2
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- 51.7
- 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
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-400, CWE-770
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
Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. From 21.2.0 until 21.2.25 and 22.2.1, RouterLink directives rendered during Node.js server-side rendering retain computed UrlTree instances for the lifetime of each request. When queryParamsHandling is set to merge or preserve, either per link or through defaultQueryParamsHandling, every rendered link can retain a copy of attacker-controlled query parameters in its UrlTree. When upstream proxies or load balancers forward oversized query strings without rejecting them at the edge, multiple affected links and overlapping renders can amplify heap use until the Node.js old-space heap is exhausted and the SSR worker terminates. Numeric query-parameter names increase allocation pressure but are not required, memory is released after rendering completes, and pure client-side SPAs are not affected. This issue is fixed in versions 21.2.25 and 22.2.1.
Source: BSI CSAF, BSI WID Portal, cvelistv5, NVD (NIST), CVE.org (MITRE), OSV (Open Source Vulnerabilities), GitHub Security Advisories
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| angular | angular |
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| Open Source | Angular |
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| npm | @angular/router |
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Vendors and products
Weakness classes (CWE)
CWE-400Uncontrolled Resource Consumption
Class
The product does not properly control the allocation and maintenance of a limited resource.
Entry at MITRE CWE-400CWE-770Allocation of Resources Without Limits or Throttling
Base
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Entry at MITRE CWE-770
References & sources
- github.comangular/angular/security/advisories/GHSA-57xq-rjx2-v5xhweb, x_refsource_CONFIRM
- github.comangular/angular/issues/70908web, x_refsource_MISC
- github.comangular/angular/pull/70953web, x_refsource_MISC
- github.comangular/angular/commit/319a3c4f3268f4f96ac4acdbb118737d2261e0beweb
- github.comangular/angularpackage
- github.comangular/angular/commit/14793bfe4b44a36ed4b7e49a60458ec711c2b41ax_refsource_MISC
- github.comangular/angular/commit/a131f77d92808ad5c2f3fa4dc6fde36825f12c5ax_refsource_MISC
- github.comangular/angular/releases/tag/v21.2.25x_refsource_MISC
- github.comangular/angular/releases/tag/v22.2.1x_refsource_MISC
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).
ReceivedGitHub
CVSS V4.0: AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness type: CWE-400, CWE-770
Description added or changed
Show 12 original changes
Individual changes of this event as published by NVD Type Action Before After Description added —Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. From 21.2.0 until 21.2.25 and 22.2.1, RouterLink directives rendered during Node.js server-side rendering retain computed UrlTree instances for the lifetime of each request. When queryParamsHandling is set to merge or preserve, either per link or through defaultQueryParamsHandling, every rendered link can retain a copy of attacker-controlled query parameters in its UrlTree. When upstream proxies or load balancers forward oversized query strings without rejecting them at the edge, multiple affected links and overlapping renders can amplify heap use until the Node.js old-space heap is exhausted and the SSR worker terminates. Numeric query-parameter names increase allocation pressure but are not required, memory is released after rendering completes, and pure client-side SPAs are not affected. This issue is fixed in versions 21.2.25 and 22.2.1.CVSS added —AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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:XWeakness type (CWE) added —CWE-400Weakness type (CWE) added —CWE-770Affected versions (publisher) added —New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/111xxx/CVE-2026-111751.json">CVE-2026-111751</a>Reference added —https://github.com/angular/angular/commit/14793bfe4b44a36ed4b7e49a60458ec711c2b41aReference added —https://github.com/angular/angular/commit/a131f77d92808ad5c2f3fa4dc6fde36825f12c5aReference added —https://github.com/angular/angular/issues/70908Reference added —https://github.com/angular/angular/pull/70953Reference added —https://github.com/angular/angular/releases/tag/v21.2.25Reference added —https://github.com/angular/angular/releases/tag/v22.2.1Reference added —https://github.com/angular/angular/security/advisories/GHSA-57xq-rjx2-v5xhSource identifier: security-advisories@github.com
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