Public vulnerability disclosure
CVE-2026-42504
Quadratic complexity in WordDecoder.DecodeHeader in mime
publishedCWE-407
Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.
Technical severity7.5 highCVSS 3.1 · ADP: CISA-ADP
Published2026-06-02Source updated 2026-11-01
Collected2026-11-022 attributed sources
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| mime Go standard library mime
https://pkg.go.dev |
≥ 0; < 1.25.11 (affected, semver) ≥ 1.26.0-0; < 1.26.4 (affected, semver) Other versions: unaffected |
CNA: Go |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | ADP: CISA-ADP |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.