CVE-2026-86112 json
BookWyrm through 0.9.1 Missing Authorization on the Favorite and Unfavorite Endpoints
published 2mo ago modified last mo. also EUVD-2026-71944
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 23%
- public exploits
- 0
- none known
Summary
BookWyrm through 0.9.1 fails to validate user visibility permissions in the Favorite and Unfavorite views, allowing authenticated attackers to favorite or unfavorite followers-only and direct statuses they cannot access. Attackers can POST to the favorite endpoint with a status ID to create unauthorized interactions, trigger ActivityPub broadcasts, and enumerate private status IDs through response differentiation.
Patch / fix
- joinbookwyrm bookwyrm 0.9.3
Is CVE-2026-86112 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
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.30% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/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
- bookwyrm-social bookwyrm
Classification
- Weakness
-
- CWE-639 Authorization Bypass Through User-Controlled Key
References
-
github.com
/geo-chen/oss/blob/main/bookwyrm.md#finding-2-authenticated-idor-in-favoriteunfavorite-allows-interaction-with
technical-description
-
github.com
/bookwyrm-social/bookwyrm/blob/v0.9.1/bookwyrm/views/interaction.py
technical-description
-
github.com
/bookwyrm-social/bookwyrm
product
-
vulncheck.com
/advisories/bookwyrm-through-0.9.1-missing-authorization-on-the-favorite-and-unfavorite-endpoints
third-party-advisory
Sources
- CVE List CVE-2026-86112
- NVD CVE-2026-86112
Fencer Intel 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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.