Vulnerability in Artifex Mupdf

CVE-2026-40505

MuPDF before 1.27 contains an ANSI injection vulnerability in mutool that allows attackers to inject arbitrary ANSI escape sequences through crafted PDF metadata fields. Attackers can embed malicious ANSI escape codes in PDF metadata that are passed unsanitized to terminal output when running mutool info, enabling them to manipulate terminal display for social engineering attacks such as presenting fake prompts or spoofed commands.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (7.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 7.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-40505: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-40505?
CVE-2026-40505 is a low-severity vulnerability in Artifex Mupdf, classified under CWE-150. CVSS score: 3.3/10. Published 2026-04-16.
How severe is CVE-2026-40505?
Low severity. CVSS v3 base score is 3.3 out of 10.