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TI-2026-74069 Aliases CVE-2026-101895

Infinite loop in Angular SSR HTML parser allows denial of service

Priority HIGH 77CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-400.

Summary

Angular and @angular/platform-server through 19.2.25, from 20.0.0 before 20.3.31, from 21.0.0 before 21.2.23, and from 22.0.0 before 22.1.6 are affected. The Domino HTML parser loops forever on an incomplete DOCTYPE that ends in whitespace at end of input (CWE-835). A remote unauthenticated attacker can trigger this through server-side HTML parsing, pinning a Node.js SSR worker at full CPU and blocking concurrent and later requests.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 20.3.31, 21.2.23, and 22.1.6, the @angular/platform-server DOM emulation parser can enter an infinite synchronous loop when Angular server-side rendering processes attacker-controlled HTML containing an incomplete DOCTYPE that ends with whitespace at end of input. In Domino lib/HTMLParser.js, after_doctype_name_state emits doctype and EOF tokens without advancing nextchar or leaving the fixed-lookahead state, so the scanner repeatedly handles the same EOF marker. A remote unauthenticated attacker can use this condition through server-side HTML parsing paths such as innerHTML binding to consume a Node.js SSR worker at full CPU, starve the event loop, and stop concurrent and subsequent requests. This issue is fixed in versions 20.3.31, 21.2.23, and 22.1.6.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00872 59th percentileScored 2026-11-07
Fix Fixed angular (angular): 20.3.31, 21.2.23, 22.1.6platform-server (@angular/): 20.3.31, 21.2.23, 22.1.6+1 more product

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
angularangularup to 19.2.25; 20.0.0 to before 20.3.31; 21.0.0 to before 21.2.23; 22.0.0 to before 22.1.620.3.31, 21.2.23, 22.1.6Patch availableCNA
angularplatform-serverup to 19.2.25; 20.0.0 to before 20.3.31; 21.0.0 to before 21.2.23; 22.0.0 to before 22.1.620.3.31, 21.2.23, 22.1.6Patch availableCNA
—@angular/platform-server (npm)22.0.0 to before 22.1.622.1.6Patch availableGHSA-f67j-2jqw-jpq7
—@angular/platform-server (npm)21.0.0 to before 21.2.2321.2.23Patch availableGHSA-f67j-2jqw-jpq7
—@angular/platform-server (npm)20.0.0 to before 20.3.3120.3.31Patch availableGHSA-f67j-2jqw-jpq7
—@angular/platform-server (npm)up to 19.2.25—No fix listedGHSA-f67j-2jqw-jpq7
  • angular Vendorangular Affected up to 19.2.25; 20.0.0 to before 20.3.31; 21.0.0 to before 21.2.23; 22.0.0 to before 22.1.6 Fixed in 20.3.31, 21.2.23, 22.1.6 Patch available CNA
  • platform-server Vendorangular Affected up to 19.2.25; 20.0.0 to before 20.3.31; 21.0.0 to before 21.2.23; 22.0.0 to before 22.1.6 Fixed in 20.3.31, 21.2.23, 22.1.6 Patch available CNA
  • @angular/platform-server (npm) Vendor— Affected 22.0.0 to before 22.1.6 Fixed in 22.1.6 Patch available GHSA-f67j-2jqw-jpq7
  • @angular/platform-server (npm) Vendor— Affected 21.0.0 to before 21.2.23 Fixed in 21.2.23 Patch available GHSA-f67j-2jqw-jpq7
  • @angular/platform-server (npm) Vendor— Affected 20.0.0 to before 20.3.31 Fixed in 20.3.31 Patch available GHSA-f67j-2jqw-jpq7
  • @angular/platform-server (npm) Vendor— Affected up to 19.2.25 Fixed in — No fix listed GHSA-f67j-2jqw-jpq7

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:angular:angular:*:*:*:*:*:*:*:*——angular
  • cpe:2.3:a:angular:angular:*:*:*:*:*:*:*:* Versions — — ·angular

Remediation

Upgrade Angular and @angular/platform-server to 20.3.31, 21.2.23, or 22.1.6, matching your release line. The sources list no fixed version for @angular/platform-server.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA angular (angular) Fixed in 20.3.31, 21.2.23, 22.1.6
  • Fix · CNA platform-server (@angular/) Fixed in 20.3.31, 21.2.23, 22.1.6
  • Fix · GHSA-f67j-2jqw-jpq7 @angular/platform-server (npm) Fixed in 22.1.6 Advisory →
  • Fix · GHSA-f67j-2jqw-jpq7 @angular/platform-server (npm) Fixed in 21.2.23 Advisory →
  • Fix · GHSA-f67j-2jqw-jpq7 @angular/platform-server (npm) Fixed in 20.3.31 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-14 Threatist record created from CVE-2026-101895
  2. 2026-10-15 CISA SSVC decision points changed
  3. 2026-10-15 Priority changed: MEDIUM → HIGH
  4. 2026-11-06 Affected versions changed · Red Hat
  5. 2026-11-06 CVSS score added · Red Hat

References

Other 8

  • TI-2026-60076 Angular: SSRF and Cross-Origin Credential Disclosure via URL Resolution Discrepancy in SSR CVSS 4.0HIGH 8.6
  • TI-2026-60080 Angular: SSR XSS via Unescaped <template> Content Across DocumentFragment Boundaries in Fallback Raw-Content Elements CVSS 4.0HIGH 8.6
  • TI-2026-60078 Angular: SSR XSS via Unescaped Processing Instruction (<?...?>) Nodes in Fallback Raw-Content Elements CVSS 4.0HIGH 8.6
  • TI-2025-38694 Server-Side Request Forgery (SSRF) in Angular SSR CVSS 4.0HIGH 8.7
  • TI-2026-22098 Angular SSR has an Open Redirect via X-Forwarded-Prefix CVSS 4.0MEDIUM 6.9
  • TI-2025-37971 A reflected cross-site scripting (XSS) vulnerability in CKeditor v46.1.0 & Angular… CVSS 3.1MEDIUM 5.4
See all 46 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences