Cyber Resilience

CVE-2026-40505

Artifex Mupdf ≤ 1.27.0

Public PoC
Published
16 April 2026
Modified
26 May 2026
Patch / advisory
View advisory
CVSS Score v4 4.8
Click a component to see what it means
Raw vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/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 Score 0.0017 6th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-40505 is a medium-severity Improper Neutralization of Escape, Meta, or Control Sequences (CWE-150) vulnerability in Artifex Mupdf. Its CVSS base score is 4.8 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Content Injection (T1659); ranked at the 6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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…

more

output when running mutool info, enabling them to manipulate terminal display for social engineering attacks such as presenting fake prompts or spoofed commands.

CWE(s)
CWE-150

Related Threats

MITRE ATT&CK Enterprise Techniques

T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-51104Same product: Artifex Mupdf
CVE-2023-51106Same product: Artifex Mupdf
CVE-2024-46657Same product: Artifex Mupdf
CVE-2026-7233Same product: Artifex Mupdf
CVE-2024-24258Same product: Artifex Mupdf
CVE-2023-51103Same product: Artifex Mupdf
CVE-2025-55780Same product: Artifex Mupdf
CVE-2023-31794Same product: Artifex Mupdf
CVE-2024-24259Same product: Artifex Mupdf
CVE-2026-25556Same product: Artifex Mupdf

Affected Assets

artifex
mupdf
≤ 1.27.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.10
  • V1.3.12

Mitigating Controls (NIST 800-53 r5) AI

SI-10 Information Input Validation good match

SI-10 requires validation/sanitization of inputs that directly stops escape/meta/control sequences from reaching downstream components.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input neutralization and escaping to prevent this class of flaw.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect the weakness but does not itself implement neutralization.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle mandates input validation and output encoding that directly neutralizes escape/meta sequences.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for controls against injection and malformed input sequences.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles reduce attack surface but do not prescribe specific neutralization techniques.

A.8.28 Secure coding partial match
prevents

Secure coding standards require proper escaping and neutralization of control characters before downstream processing.

References