SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-103937

From 13.0.0 until 2025.4.1 and from 2025.5.0 until 2026.7.0, cleanup processing may not execute during file uploads.

HIGH 8.7EPSS 0.50%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.50%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Misskey is an open source, federated social media platform. From 13.0.0 until 2025.4.1 and from 2025.5.0 until 2026.7.0, cleanup processing may not execute during file uploads. Repeated uploads can exhaust storage or file descriptors and deny service regardless of whether federation is enabled. This issue is fixed in version 2026.7.0.

CVSS 4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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/M
EPSS
0.50% probability · 43th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-459
Source
security-advisories@github.com
EPSS trend
0%3%5%14 October 2026: 0.50%26 October 2026: 0.50%14 October 202626 October 2026

EPSS moved from 0.5% on 14 October 2026 to 0.5% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.