{"id":"CVE-2026-56306","aliases":["EUVD-2026-38369","GHSA-42vv-8j94-24wj"],"status":"published","title":"Capgo - Subkey Enforcement Bypass via x-limited-key-id Header Parsing","description":"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.","severity":{"version":"4.0","score":5.3,"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","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00302,"percentile":0.2319,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-20"],"published":"2026-06-22T21:04:46Z","modified":"2026-10-28T02:30:58Z","products":[{"vendor":"cap-go","product":"capgo"},{"vendor":"capgo","product":"capgo"}],"references":[{"url":"https://github.com/Cap-go/capgo/security/advisories/GHSA-42vv-8j94-24wj","tags":["vendor-advisory","exploit","advisory"]},{"url":"https://www.vulncheck.com/advisories/capgo-subkey-enforcement-bypass-via-x-limited-key-id-header-parsing","tags":["third-party-advisory","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56306.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56306","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-56306","title":"Capgo - Subkey Enforcement Bypass via x-limited-key-id Header Parsing","description":"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.","status":"published","published":"2026-06-22T21:04:46.832Z","modified":"2026-06-23T12:11:26.119Z","cvss":[{"version":"4.0","score":5.3,"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","level":"medium","assessor":"cna"},{"version":"3.1","score":6.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T13:37:02.780526Z"}],"euvd":[{"id":"EUVD-2026-38369","description":"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.","status":"published","published":"2026-06-22T21:04:46Z","modified":"2026-06-23T12:11:26Z","cvss":[{"version":"4.0","score":5.3,"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","level":"medium"}],"updated_at":"2026-11-02T18:20:33.850201Z"}],"nvd":[{"id":"CVE-2026-56306","description":"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.","status":"published","published":"2026-06-22T22:16:51.333Z","modified":"2026-10-25T23:10:00.167Z","cvss":[{"version":"4.0","score":5.3,"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:12:25.288279Z"}],"osv":[{"id":"CVE-2026-56306","title":"Capgo - Subkey Enforcement Bypass via x-limited-key-id Header Parsing","description":"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.","status":"published","published":"2026-06-22T21:04:46.832Z","modified":"2026-10-28T02:30:58.270969977Z","cvss":[{"version":"4.0","score":5.3,"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","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:45:11.609219Z"}]}}