Dashboard / CVE-2026-41259

CVE-2026-41259

HIGH
MEDIUM Priority: 0.02 BB Relevance: 76/100
Published: 2026-04-23 Modified: 2026-11-11 First seen: 2026-11-11 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: X
AT: Present
VC: None
VI: High
VA: None

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.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
joinmastodon mastodon < 4.3.22

References & Advisories (1)

Bug Bounty Relevance

76 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

8.2 / 10.0 v4.0
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

EPSS — Exploitation Probability

0.21%
Raw Score 0.002130
Percentile 11.7%
Date 2026-11-13

EPSS Trend

2026-11-13
0.00213
2026-11-12
0.00213
2026-11-10
0.00213

Intelligence Sources

nvd ref →

External Links