PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-50557 angular CVE debrief

CVE-2026-50557 is a medium-severity vulnerability in Angular that allows an attacker to bypass element and attribute sanitization/validation, leading to client-side Cross-Site Scripting (XSS). The issue arises from the improper identification of namespaced script elements and inconsistent handling of attributes within namespaced elements. This vulnerability affects various versions of Angular, including those prior to 22.0.0-rc.2, 21.2.15, 20.3.22, and 19.2.22. The vulnerability has been fixed in the mentioned versions. An attacker can inject or supply a template/tag structure with custom namespaces to exploit this vulnerability. The CVSS score for this vulnerability is 5.3, indicating a medium severity level.

Vendor
angular
Product
Unknown
CVSS
MEDIUM 5.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-22
Original CVE updated
2026-07-09
Advisory published
2026-06-22
Advisory updated
2026-07-09

Who should care

Developers and administrators using Angular versions prior to 22.0.0-rc.2, 21.2.15, 20.3.22, and 19.2.22 should be aware of this vulnerability and take necessary actions to upgrade to the fixed versions. Additionally, security teams and vulnerability managers should prioritize this medium-severity vulnerability and ensure that affected systems are patched.

Technical summary

The vulnerability is caused by the improper identification of namespaced script elements (e.g., <svg:script> or <:svg:script>) by the Angular template preparser. This allows them to pass through template compilation without being stripped. Furthermore, security context schema mappings for element attributes do not consistently handle attributes within namespaced elements (like SVG and MathML), creating gaps where malicious namespaced attributes could bypass runtime and compile-time sanitizers. An attacker can exploit this vulnerability by injecting or supplying a template/tag structure with custom namespaces, enabling them to bypass Angular's script-stripping logic and attribute sanitizers, leading to client-side Cross-Site Scripting (XSS).

Defensive priority

This medium-severity vulnerability requires prompt attention from developers and administrators using affected Angular versions. Upgrading to the fixed versions (22.0.0-rc.2, 21.2.15, 20.3.22, and 19.2.22) is crucial to prevent potential client-side XSS attacks.

Recommended defensive actions

  • Upgrade to Angular version 22.0.0-rc.2 or later
  • Upgrade to Angular version 21.2.15 or later
  • Upgrade to Angular version 20.3.22 or later
  • Upgrade to Angular version 19.2.22 or later
  • Review and update affected systems and applications
  • Monitor for potential exploitation attempts

Evidence notes

The CVE-2026-50557 vulnerability is documented in the official CVE record and NVD detail pages. The vulnerability affects various versions of Angular, and the fixes are available in the mentioned versions. The CVSS score for this vulnerability is 5.3, indicating a medium severity level.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-50557 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-50557

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-50557 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-50557

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.