SecuriTricks - CVE-2026-41259

Description

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.

Product(s) Impacted

Vendor	Product	Versions
Joinmastodon	Mastodon	4.3.22, 4.4.16, 4.5.9

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-841

Improper Enforcement of Behavioral Workflow

The product supports a session in which more than one behavior must be performed by an actor, but it does not properly ensure that the actor performs the behaviors in the required sequence.

*CPE(s)

Affected systems and software identified for this CVE.

Type	Vendor	Product	Version	Update	Edition	Language	Software Edition	Target Software	Target Hardware	Other Information
a	joinmastodon	mastodon	4.3.22	/	/	/	/	/	/	/
a	joinmastodon	mastodon	4.4.16	/	/	/	/	/	/	/
a	joinmastodon	mastodon	4.5.9	/	/	/	/	/	/	/

References

https://github.com/mastodon/mastodon/security/advisories/GHSA-5r37-qpwq-2jhh

CVSS Score

8.2 / 10

CVSS Data - 4.0

Attack Vector: NETWORK
Attack Complexity: LOW
Attack Requirements: PRESENT
Privileges Required: NONE
User Interaction: NONE
Scope:
Confidentiality Impact: NONE
Integrity Impact: HIGH
Availability Impact: NONE
Exploit Maturity: NOT_DEFINED

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

View Vector String

Timeline

Published: April 23, 2026, 7:17 p.m.
Last Modified: April 24, 2026, 2:50 p.m.

Status : Awaiting Analysis

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

[email protected]

CVE-2026-41259