FlaskBB: SSRF in get_image_info() via unrestricted avatar URL

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS

• CVE-2026-46556: 0.35% estimated exploitation activity in the next 30 days; percentile 29.13 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

###Summary A Server-Side Request Forgery (SSRF) vulnerability in getimageinfo() allows any authenticated user to force the server to send HTTP requests to arbitrary internal endpoints, including cloud metadata services (e.g., AWS 169.254.169.254). This is a blind SSRF with confirmed internal port scanning and internal API triggering capabilities. CVSS 6.5 Medium. ###Details In flaskbb/utils/helpers.py (line 571), the url parameter is passed directly to requests.get(url, stream=True) without any validation of scheme, host, or IP address. Attack chain: ###PoC submit.zip Log in to FlaskBB as any user Navigate to Settings → User Details Enter http://169.254.169.254/latest/meta-data/ as the avatar URL Submit the form The server sends a GET request to the internal metadata endpoint Three exploitation channels confirmed: Server-side request: Captured on mock metadata server Internal port scan: checkimage() returns distinct errors (CONNREFUSED, NOCONTENTLENGTH, TYPENOTALLOWED, SUCCESS) that…

Published by the source

21 May 2026, 20:42 UTC

Last modified by the source

13 Jul 2026, 16:42 UTC

Source last checked

26 Oct 2026, 13:41 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-xq32-9g7q-7297

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-xq32-9g7q-7297

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# Patch Next advisory brief: CVE-2026-46556

Advisory: FlaskBB: SSRF in get_image_info() via unrestricted avatar URL
IDs: CVE-2026-46556, GHSA-xq32-9g7q-7297
Record: https://patchnext.com/advisories/cve-2026-46556 (revision 2, source checked 26 Oct 2026, 13:41 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI flaskbb: affected <= 2.2.0

## Suggested inspection (read-only)
- `python -m pip show flaskbb`: prints the installed version. Run with the environment that serves production active.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on flaskbb.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-xq32-9g7q-7297 (OSV record GHSA-xq32-9g7q-7297 lists affected ranges: PyPI flaskbb >=0 <=2.2.0)
- Verified: https://github.com/advisories/GHSA-xq32-9g7q-7297 (GitHub-reviewed advisory GHSA-xq32-9g7q-7297 lists affected ranges: PyPI flaskbb >=0 <=2.2.0)

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