CVE-2026-56249 json
Capgo - Unauthorized Channel Overwrite and Ownership Takeover via POST /channel Name Collision
published 2026-06-30 4 mo ago modified 2026-07-01 4 mo ago also EUVD-2026-40430
- cvss
- 7.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 30%
- public exploits
- 0
- none known
Summary
Capgo before 12.128.2 contains an authorization bypass vulnerability in the channel creation endpoint that allows authenticated users to overwrite existing channels by reusing their names. Attackers with app.create_channel permission can exploit a logic mismatch between existence validation and upsert operations to reassign channel ownership and modify critical production channel configurations.
Patch / fix
- Capgo Capgo 12.128.2
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.36% chance of exploitation in the next 30 days, higher than 30% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/Cap-go/capgo/security/advisories/GHSA-vj24-j594-3wv3 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.2 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L |
| CNA | 4.0 | 7.2 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/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-285 Improper Authorization
References
-
github.com
/Cap-go/capgo/security/advisories/GHSA-vj24-j594-3wv3
vendor-advisory, exploit
-
vulncheck.com
/advisories/capgo-unauthorized-channel-overwrite-and-ownership-takeover-via-post-channel-name-collision
third-party-advisory
Sources
- CVE List CVE-2026-56249
- NVD CVE-2026-56249
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.