CVE-2026-42504: CWE-407: Inefficient Algorithmic Complexity in Go standard library mime
CVE-2026-42504 is a high-severity vulnerability in the Go standard library's mime package. It involves inefficient algorithmic complexity when decoding MIME headers containing many invalid encoded-words, leading to excessive CPU consumption. This can cause denial of service through resource exhaustion but does not affect confidentiality or integrity. No official patch or remediation guidance is currently available. Users should monitor vendor advisories for updates.
AI Analysis
Technical Summary
This vulnerability in the Go standard library mime package (CVE-2026-42504) arises from inefficient algorithmic complexity during the decoding of MIME headers with numerous invalid encoded-words. The excessive CPU usage can result in denial of service conditions. The issue does not compromise data confidentiality or integrity. Affected versions include 0, 1.26.0-0, and versions from 1.26.0 up to but not including 1.26.1. There is no official remediation or patch available at this time.
Potential Impact
The vulnerability can cause denial of service by exhausting CPU resources when processing specially crafted MIME headers with many invalid encoded-words. There is no impact on confidentiality or integrity of data.
Mitigation Recommendations
No official patch or remediation guidance is currently available. Users should monitor vendor advisories for updates and consider implementing application-level protections to limit processing of untrusted MIME headers until a fix is released.
CVE-2026-42504: CWE-407: Inefficient Algorithmic Complexity in Go standard library mime
Description
CVE-2026-42504 is a high-severity vulnerability in the Go standard library's mime package. It involves inefficient algorithmic complexity when decoding MIME headers containing many invalid encoded-words, leading to excessive CPU consumption. This can cause denial of service through resource exhaustion but does not affect confidentiality or integrity. No official patch or remediation guidance is currently available. Users should monitor vendor advisories for updates.
CVSS v3.1
Score 7.5high
Affected software
pkg:golang/github.com/golang/go/src/mimeRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in the Go standard library mime package (CVE-2026-42504) arises from inefficient algorithmic complexity during the decoding of MIME headers with numerous invalid encoded-words. The excessive CPU usage can result in denial of service conditions. The issue does not compromise data confidentiality or integrity. Affected versions include 0, 1.26.0-0, and versions from 1.26.0 up to but not including 1.26.1. There is no official remediation or patch available at this time.
Potential Impact
The vulnerability can cause denial of service by exhausting CPU resources when processing specially crafted MIME headers with many invalid encoded-words. There is no impact on confidentiality or integrity of data.
Mitigation Recommendations
No official patch or remediation guidance is currently available. Users should monitor vendor advisories for updates and consider implementing application-level protections to limit processing of untrusted MIME headers until a fix is released.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Go
- Date Reserved
- 2026-04-28T00:21:12.792Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Gcve Source
- db.gcve.eu
Threat ID: 6a1f872ae29bf47b5044bf13
Added to database: 06/03/2026, 01:45:14 UTC
Last enriched: 07/30/2026, 21:03:00 UTC
Last updated: 07/31/2026, 21:27:09 UTC
Views: 426
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