CVE-2026-42504

Aliases:GO-2026-5038BIT-golang-2026-42504
Advisory lineage Upstream: 0 Downstream: 22
Awaiting Analysis
Published: 02 Jun 2026, 22:01
Last modified:22 Jul 2026, 20:58

Vulnerability Summary

Overall Risk (default)
medium
30/100
CVSS Score
7.5 HIGH
v3.1 (cve.org)
EPSS Score
0.56% LOW
1% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

02 Jun 2026, 22:01
Published
Vulnerability first disclosed
22 Jul 2026, 20:58
Last Modified
Vulnerability information updated

Description

Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.

CVSS Metrics

  • v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.56%• Percentile: 43%

Techniques & Countermeasures

  • CWE-407•Inefficient Algorithmic Complexity

    An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.

Affected Systems

  • go standard library•mime

    < 1.25.11 | ≥ 1.26.0-0, < 1.26.4

  • Go•stdlib

    ≥ 1.26.0-0, < 1.26.4

References (4)