CVE-2026-59825
Mastodon: Unwanted deactivation of SSL/TLS certificate verification
Description
Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.19 and from 4.5.0 until 4.5.12, Mastodon's app/models/concerns/user/ldap_authenticable.rb mutates OpenSSL::SSL::SSLContext::DEFAULT_PARAMS when LDAP authentication uses LDAP_TLS_NO_VERIFY=true, disabling SSL and TLS certificate verification globally for requests made by puma web processes while sidekiq background jobs remain unaffected. This issue is fixed in versions 4.4.19 and 4.5.12.
INFO
Published Date :
Aug. 18, 2026, 3:16 p.m.
Last Modified :
Aug. 18, 2026, 4:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE |
Solution
- Update Mastodon to version 4.4.19 or later.
- Update Mastodon to version 4.5.12 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-59825.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-59825 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-59825
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-59825 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-59825 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 18, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-59825', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-18T15:51:09.488217Z'} -
New CVE Received by [email protected]
Aug. 18, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'mastodon', 'product': 'mastodon', 'versions': [{'status': 'affected', 'version': '< 4.4.19'}, {'status': 'affected', 'version': '>= 4.5.0, < 4.5.12'}]}] Added Description Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.19 and from 4.5.0 until 4.5.12, Mastodon's app/models/concerns/user/ldap_authenticable.rb mutates OpenSSL::SSL::SSLContext::DEFAULT_PARAMS when LDAP authentication uses LDAP_TLS_NO_VERIFY=true, disabling SSL and TLS certificate verification globally for requests made by puma web processes while sidekiq background jobs remain unaffected. This issue is fixed in versions 4.4.19 and 4.5.12. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-295 Added Reference https://github.com/mastodon/mastodon/commit/2ccb6ef277e725d1932295690cf8ab9d3dc03149 Added Reference https://github.com/mastodon/mastodon/commit/5748d0b16ea09001e0933f76c7afe814e09652ef Added Reference https://github.com/mastodon/mastodon/commit/761c61b42590a2fd91442fc15a0a7583e48bbea4 Added Reference https://github.com/mastodon/mastodon/pull/39571 Added Reference https://github.com/mastodon/mastodon/releases/tag/v4.4.19 Added Reference https://github.com/mastodon/mastodon/releases/tag/v4.5.12 Added Reference https://github.com/mastodon/mastodon/security/advisories/GHSA-3rhr-8phh-jm86