CVE-2026-40026

MediumPublic PoC

Published: 08 April 2026

Published

08 April 2026

Modified

17 April 2026

KEV Added

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Patch

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CVSS Score 4.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L

EPSS Score 0.0001 2.3th percentile

Risk Priority 9 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-40026 is a medium-severity Out-of-bounds Read (CWE-125) vulnerability in Sleuthkit The Sleuth Kit. Its CVSS base score is 4.4 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Malicious File (T1204.002); ranked at the 2.3th 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 are NIST 800-53 RA-5 (Vulnerability Monitoring and Scanning) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Malicious File (T1204.002). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match

prevent

Mandates timely identification, reporting, and correction of software flaws like the out-of-bounds read and infinite loop in Sleuth Kit's ISO9660 parser via patching.

RA-5 Vulnerability Monitoring and Scanning good match

detect

Requires vulnerability scanning and monitoring of sources to identify and prioritize remediation for CVEs such as CVE-2026-40026 in deployed Sleuth Kit instances.

SI-10 Information Input Validation partial match

prevent

Enforces validation of untrusted inputs like len_id, len_des, and len_src fields from ISO images to prevent buffer overreads in filesystem parsers.

MITRE ATT&CK Enterprise TechniquesAI

T1204.002 Malicious File Execution

An adversary may rely upon a user opening a malicious file in order to gain execution.

attack.mitre.org →

Why these techniques?

The out-of-bounds read and infinite loop in the ISO9660 parser are triggered when a user opens a malicious ISO image with the vulnerable Sleuth Kit software, directly mapping to user execution of a malicious file.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

The Sleuth Kit through 4.14.0 contains an out-of-bounds read vulnerability in the ISO9660 filesystem parser where the parse_susp() function trusts len_id, len_des, and len_src fields from the disk image to memcpy data into a stack buffer without verifying that the…

source data falls within the parsed SUSP block. An attacker can craft a malicious ISO image that causes reads past the end of the SUSP data buffer, and a zero-length SUSP entry can trigger an infinite parsing loop.

Deeper analysisAI

The Sleuth Kit through version 4.14.0 is affected by an out-of-bounds read vulnerability (CWE-125) in its ISO9660 filesystem parser. The issue resides in the parse_susp() function, which trusts the len_id, len_des, and len_src fields from a disk image without verifying that the source data falls within the parsed SUSP block before using memcpy to copy data into a stack buffer. This allows reads past the end of the SUSP data buffer. Additionally, a zero-length SUSP entry can trigger an infinite parsing loop.

Exploitation requires local access (AV:L) with low attack complexity (AC:L), no privileges (PR:N), and user interaction (UI:R), such as opening a malicious ISO image with the affected software. Successful exploitation can result in low-impact confidentiality loss (C:L) through potential information disclosure from the out-of-bounds read, or low-impact availability disruption (A:L) via denial of service from the buffer overread or infinite loop, with no integrity impact (I:N) and unchanged scope (S:U). The overall CVSS v3.1 base score is 4.4 (Medium).

Mitigation is addressed in patches referenced in the Sleuth Kit GitHub repository, including commit a95b0ac21733b059a517aaefa667a17e1bcbdee1 and pull request #3445. Additional details are available in advisories from VulnCheck and other sources like mobasi.ai/sentinel. Security practitioners should update to a patched version of Sleuth Kit beyond 4.14.0 when analyzing disk images.