CVE-2026-56306 PUBLISHED

Capgo - Subkey Enforcement Bypass via x-limited-key-id Header Parsing

Assigner: VulnCheck
Reserved: 20.06.2026 Published: 22.06.2026 Updated: 23.06.2026

Capgo before 12.128.2 contains a weak parsing vulnerability in the x-limited-key-id header that allows attackers to bypass subkey enforcement by submitting malformed values, zero, or duplicate headers that result in NaN or falsy values. Remote attackers can manipulate the x-limited-key-id header to disable limited key scoping and execute requests using the main API key context instead of restricted subkey permissions.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
CVSS Score: 5.3

Product Status

Vendor Capgo
Product Capgo
Versions Default: unaffected
  • affected from 0 to 12.128.2 (excl.)
  • Version 12.128.2 is unaffected

Credits

  • Judel777 reporter

References

Problem Types

  • Improper Input Validation CWE