libarchive on 32-bit ISO9660 Image Parser heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k5.44-

Summaryinfo

A vulnerability, which was classified as critical, was found in libarchive on 32-bit. This issue affects some unknown processing of the component ISO9660 Image Parser. Executing a manipulation can lead to heap-based overflow. This vulnerability is registered as CVE-2026-5121. It is possible to launch the attack remotely. No exploit is available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability classified as critical was found in libarchive on 32-bit (affected version not known). This vulnerability affects some unknown functionality of the component ISO9660 Image Parser. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A flaw was found in libarchive. On 32-bit systems, an integer overflow vulnerability exists in the zisofs block pointer allocation logic. A remote attacker can exploit this by providing a specially crafted ISO9660 image, which can lead to a heap buffer overflow. This could potentially allow for arbitrary code execution on the affected system.

The advisory is shared for download at access.redhat.com. This vulnerability was named CVE-2026-5121 since 03/30/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-17073). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: github.com

Timelineinfo

03/30/2026 Advisory disclosed
03/30/2026 +0 days CVE reserved
03/30/2026 +0 days VulDB entry created
03/30/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2026-5121 (🔒)
GCVE (CVE): GCVE-0-2026-5121
GCVE (VulDB): GCVE-100-354160
EUVD: 🔒

Entryinfo

Created: 03/30/2026 11:56
Updated: 03/30/2026 17:21
Changes: 03/30/2026 11:56 (55), 03/30/2026 17:21 (1)
Complete: 🔍
Cache ID: 216:045:103

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