Skip to main content

Mastodon CVE-2026-41259

| EUVDEUVD-2026-25282 HIGH
Improper Enforcement of Behavioral Workflow (CWE-841)
2026-04-23 security-advisories@github.com
Information Disclosure Mastodon
8.2
CVSS 4.0 · GitHub Advisory
Share

Severity by source

GitHub Advisory PRIMARY
8.2 HIGH
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/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

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/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
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
X

Lifecycle Timeline

4
Patch released
Apr 28, 2026 - 18:50 nvd
Patch available
Patch available
Apr 23, 2026 - 21:01 EUVD
EUVD ID Assigned
Apr 23, 2026 - 19:27 euvd
EUVD-2026-25282
CVE Published
Apr 23, 2026 - 19:17 nvd
HIGH 8.2

DescriptionGitHub Advisory

Mastodon is a free, open-source social network server based on ActivityPub. Prior to v4.5.9, v4.4.16, and v4.3.22, Mastodon allows restricting new user sign-up based on e-mail domain names, and performs basic validation on e-mail addresses, but fails to restrict characters that are interpreted differently by some mailing servers. This vulnerability is fixed in v4.5.9, v4.4.16, and v4.3.22.

Analysis

Mastodon is a free, open-source social network server based on ActivityPub. Prior to v4.5.9, v4.4.16, and v4.3.22, Mastodon allows restricting new user sign-up based on e-mail domain names, and performs basic validation on e-mail addresses, but fails to restrict characters that are interpreted differently by some mailing servers. This vulnerability is fixed in v4.5.9, v4.4.16, and v4.3.22.

More in Mastodon

View all
CVE-2022-46405 HIGH POC
7.5 Dec 04

Mastodon through 4.0.2 allows attackers to cause a denial of service (large Sidekiq pull queue) by creating bot accounts
CVE-2024-25618 HIGH POC
7.4 Feb 14

Mastodon is a free, open-source social network server based on ActivityPub. Rated high severity (CVSS 7.4), this vulnera
CVE-2023-28853 MEDIUM POC
6.5 Apr 04

Mastodon is a free, open-source social network server based on ActivityPub Mastodon allows configuration of LDAP for aut
CVE-2023-36460 CRITICAL
9.9 Jul 06

Mastodon is a free, open-source social network server based on ActivityPub. Rated critical severity (CVSS 9.9), this vul
CVE-2024-23832 CRITICAL
9.8 Feb 01

Mastodon is a free, open-source social network server based on ActivityPub Mastodon allows configuration of LDAP for aut
CVE-2022-2166 CRITICAL
9.8 Nov 16

Improper Restriction of Excessive Authentication Attempts in GitHub repository mastodon/mastodon prior to 4.0.0. Rated c
CVE-2026-46348 HIGH
8.7 Jun 24

Server-Side Request Forgery in Mastodon before 4.5.10, 4.4.17, and 4.3.23 lets attackers coerce the server into issuing

CVE-2026-47389 HIGH
8.6 Jun 24

Server-side request forgery in Mastodon (versions before 4.5.10, 4.4.17, and 4.3.23) lets an attacker who controls autho
CVE-2026-27468 HIGH
8.2 Feb 24

Unauthenticated attackers can bypass FASP administrator approval in Mastodon 4.4.0-4.4.13 and 4.5.0-4.5.6 to subscribe t
CVE-2024-37903 HIGH
8.2 Jul 05

Mastodon is a self-hosted, federated microblogging platform. Rated high severity (CVSS 8.2), this vulnerability is remot
CVE-2024-25623 HIGH
7.7 Feb 19

Mastodon is a free, open-source social network server based on ActivityPub. Rated high severity (CVSS 7.7), this vulnera
CVE-2026-50129 HIGH
7.5 Jun 24

Denial of service in Mastodon affects all self-hosted instances prior to 4.5.11, 4.4.18, and 4.3.24, where the math cont

Same weakness CWE-841 – Improper Enforcement of Behavioral Workflow

View all
CVE-2023-4181 CRITICAL POC
9.8
CVE-2024-46307 HIGH POC
7.5
CVE-2026-30574 HIGH POC
7.5
CVE-2025-52469 HIGH POC
7.1
CVE-2024-6128 MEDIUM POC
6.9
CVE-2026-3130 CRITICAL
9.8
CVE-2022-2105 CRITICAL
9.1
CVE-2026-43974 HIGH
8.7

Same technique Information Disclosure

View all
CVE-2013-2251 CRITICAL POC
9.8
CVE-2017-5638 CRITICAL POC
9.8
CVE-2025-24813 CRITICAL POC
9.8
CVE-2015-1701 HIGH POC
7.8
CVE-2017-0147 HIGH POC
7.5
CVE-2014-6324 HIGH POC
8.8
CVE-2023-7028 CRITICAL POC
10.0
CVE-2017-0213 HIGH POC
7.3

Share

CVE-2026-41259 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy