CVE-2026-103043: Inefficient Regular Expression Complexity in alexcorvi anchorme
anchorme through 3.0.8 contains a regular expression denial of service vulnerability in the IPv6 host extraction regex due to catastrophic backtracking. Attackers can supply specially crafted input strings with repeated patterns to cause exponential regex engine backtracking, blocking the Node.js event loop and denying service to other requests.
AI Analysis
Technical Summary
CVE-2026-103043 identifies a ReDoS vulnerability in the anchorme library (versions up to 3.0.8) caused by inefficient regular expression complexity in the IPv6 host extraction regex. The regex can exhibit catastrophic backtracking when processing maliciously crafted input strings containing repeated patterns, leading to exponential processing time. This behavior blocks the Node.js event loop, resulting in denial of service conditions for other requests handled by the same event loop.
Potential Impact
Successful exploitation can cause denial of service by blocking the Node.js event loop, preventing the application from processing other requests. This can degrade availability of services relying on anchorme for URL or host extraction.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input with anchorme or implement input validation to limit repeated patterns in IPv6 host strings.
CVE-2026-103043: Inefficient Regular Expression Complexity in alexcorvi anchorme
Description
anchorme through 3.0.8 contains a regular expression denial of service vulnerability in the IPv6 host extraction regex due to catastrophic backtracking. Attackers can supply specially crafted input strings with repeated patterns to cause exponential regex engine backtracking, blocking the Node.js event loop and denying service to other requests.
CVSS v4.0
Score 8.7high
Affected software
alexcorvi
anchorme
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-103043 identifies a ReDoS vulnerability in the anchorme library (versions up to 3.0.8) caused by inefficient regular expression complexity in the IPv6 host extraction regex. The regex can exhibit catastrophic backtracking when processing maliciously crafted input strings containing repeated patterns, leading to exponential processing time. This behavior blocks the Node.js event loop, resulting in denial of service conditions for other requests handled by the same event loop.
Potential Impact
Successful exploitation can cause denial of service by blocking the Node.js event loop, preventing the application from processing other requests. This can degrade availability of services relying on anchorme for URL or host extraction.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input with anchorme or implement input validation to limit repeated patterns in IPv6 host strings.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-29T22:17:06.983Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abc4489680226ef6869e5b9
Added to database: 09/29/2026, 23:06:49 UTC
Last enriched: 09/29/2026, 23:21:14 UTC
Last updated: 09/30/2026, 03:03:19 UTC
Views: 8
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