Cyber Resilience

CVE-2026-44713

High

Published: 27 May 2026

Published
27 May 2026
Modified
28 May 2026
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0016 5.4th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-44713 is a high-severity OS Command Injection (CWE-78) vulnerability. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Unix Shell (T1059.004); ranked at the 5.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability details

pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.8.7, src/tmux.c reads the user's $TMUX environment variable, splits it on commas, and interpolates the socket-path component directly into a shell command passed to popen(). Because the value…

more

is placed inside double-quotes without sanitisation, any value containing " terminates the quoted string and injects arbitrary shell syntax. popen() runs as root inside the PAM stack. This vulnerability is fixed in 0.8.7.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Unsanitized $TMUX env var interpolated into popen() shell command executed as root in PAM auth flow directly enables Unix shell command injection (T1059.004) for local privilege escalation (T1068).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-35582Shared CWE-116, CWE-78
CVE-2026-26318Shared CWE-78
CVE-2026-5208Shared CWE-78
CVE-2025-70329Shared CWE-78
CVE-2024-49563Shared CWE-78
CVE-2026-33641Shared CWE-78
CVE-2026-22277Shared CWE-78
CVE-2024-49565Shared CWE-78
CVE-2026-42924Shared CWE-78
CVE-2025-66209Shared CWE-78

Affected Assets

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

addresses: CWE-78

Validates inputs to block special elements that would alter OS command execution.

addresses: CWE-116

Validating that output matches expected content directly mitigates failures to properly encode or escape data for its destination context.

References