CVE-2026-56306

Summary

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.

Affected Software

Weaknesses

• CWE-20: Improper Input Validation

ADP Enrichment

CISA ADP Vulnrichment

• SSVC:
• Exploitation: poc
  • Automatable: no
  • Technical Impact: partial

Additional References

• https://github.com/Cap-go/capgo/security/advisories/GHSA-42vv-8j94-24wj

References

• https://github.com/Cap-go/capgo/security/advisories/GHSA-42vv-8j94-24wj
• https://www.vulncheck.com/advisories/capgo-subkey-enforcement-bypass-via-x-limited-key-id-header-parsing

• ←Previous
• Next→