CVE-2025-67500 json
Mastodon Error Handling Discrepancy Enables Private Status Existence Enumeration
published 2025-12-09 10 mo ago modified 2026-10-14 25 d ago also BIT-mastodon-2025-67500 , EUVD-2025-202338 , GHSA-gwhw-gcjx-72v8
- cvss
- 3.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 13%
- public exploits
- 0
- none known
Summary
Mastodon is a free, open-source social network server based on ActivityPub. Versions 4.2.27 and prior, 4.3.0-beta.1 through 4.3.14, 4.4.0-beta.1 through 4.4.9, 4.5.0-beta.1 through 4.5.2 have discrepancies in error handling which allow checking whether a given status exists by sending a request with a non-English Accept-Language header. Using this behavior, an attacker who knows the identifier of a particular status they are not allowed to see can confirm whether this status exists or not. This cannot be used to learn the contents of the status or any other property besides its existence. This issue is fixed in versions 4.2.28, 4.3.15, 4.4.10 and 4.5.3.
Patch / fix
- bitnami mastodon 4.2.28, 4.3.15, 4.4.10, 4.5.3
- joinmastodon mastodon 4.2.28, 4.3.15, 4.4.10, 4.5.3
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 10 mo ago
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
| NVD | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
| OSV | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | mastodon | <4.2.28 >=4.3.0, <4.3.15 >=4.4.0, <4.4.10 >=4.5.0, <4.5.3 |
4.2.28 4.3.15 4.4.10 4.5.3 |
Affected products
- mastodon mastodon
Classification
- Weakness
-
- CWE-204 Observable Response Discrepancy
References
Sources
- CVE List CVE-2025-67500
- NVD CVE-2025-67500
- OSV BIT-mastodon-2025-67500
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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.