CVE-2026-22659 json
FlaskBB Authorization Bypass via Topic ID Manipulation
published 3mo ago modified 3mo ago also EUVD-2026-42878
- cvss
- 8.1
- 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 44%
- public exploits
- 0
- none known
Summary
FlaskBB through 2.2.0, fixed in commit acc88cf, contains an authorization bypass vulnerability that allows authenticated moderators to perform unauthorized actions on topics in forums they do not control by submitting crafted topic ID lists. Attackers can include a low-ID topic from a permitted forum as an anchor in a batch request, causing the permission check applied only to the first result to pass, and then execute lock, unlock, delete, or hide actions against topics in unmoderated forums.
Patch / fix
Is CVE-2026-22659 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3mo ago
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/flaskbb/flaskbb/security/advisories/GHSA-9rjj-9p2h-6c55 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:N/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
| CNA | 4.0 | 7.2 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/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
- flaskbb flaskbb
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
Sources
- CVE List CVE-2026-22659
- NVD CVE-2026-22659
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