CVE-2026-56306CWE-20

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

Medium · published June 22, 2026

CVSS v4.0
5.3
EPSS
0%
Percentile
26.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
5.3 · MEDIUM
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
EPSS
0.00345 · 26.8th percentile
Weakness
CWE-20 · Improper Input Validation
Published
2026-06-22T21:04Z
EPSS history
Timeline
  • 22 JUN 21:04Z
    Capgo - Subkey Enforcement Bypass via x-limited-key-id Header Parsing
    cvelistv5