CVE-2026-56306

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.

CVSS v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-22 22:16

Updated : 2026-06-23 14:52

NVD link : CVE-2026-56306

Mitre link : CVE-2026-56306

CVE.ORG link : CVE-2026-56306

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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