CVE-2026-56300 json
Capgo - Unauthenticated API Key Validity and Permission Oracle via RPC Functions
published 4mo ago modified 4mo ago also EUVD-2026-40435
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 40%
- public exploits
- 0
- none known
Summary
Capgo before 12.128.2 contains unauthenticated security definer RPC functions get_user_id and get_org_perm_for_apikey that expose API key validity oracles and user UUID disclosure. Unauthenticated attackers using the public API key can validate leaked keys, enumerate users and apps, and determine permission levels, significantly increasing the actionability of compromised credentials.
Patch / fix
- Capgo Capgo 12.128.2
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.46% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/Cap-go/capgo/security/advisories/GHSA-7r6g-whg3-5mm4 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/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 |
Affected products
- Capgo Capgo
Classification
- Weakness
-
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
References
-
github.com
/Cap-go/capgo/security/advisories/GHSA-7r6g-whg3-5mm4
vendor-advisory, exploit
-
vulncheck.com
/advisories/capgo-unauthenticated-api-key-validity-and-permission-oracle-via-rpc-functions
third-party-advisory
Sources
- CVE List CVE-2026-56300
- NVD CVE-2026-56300
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