Xen libfsimage iso9660 driver/Rock Ridge extension input validation

Summaryinfo

A vulnerability marked as very critical has been reported in Xen libfsimage. The impacted element is an unknown function of the component iso9660 driver/Rock Ridge extension. This manipulation causes input validation. This vulnerability appears as CVE-2026-62424. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability has been found in Xen libfsimage (the affected version is unknown) and classified as very critical. Affected by this vulnerability is an unknown code of the component iso9660 driver/Rock Ridge extension. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] The directory and Rock Ridge / SUSP walk in libfsimage's iso9660 driver derives several lengths directly from attacker-controlled on-disk fields without validating them: * The directory loop itself assumes a good record length. This is CVE-2026-42494. * The calculation of the System Use area may underflow. This is CVE-2026-42495. * The Rock Ridge extension loop assumes a good (inner) record length. This is CVE-2026-62423. * The Rock Ridge NM record processing assumes a good entry length. This is CVE-2026-62424. * The Rock Ridge CE record processing assumes a good size and offset. This is CVE-2026-62425.

It is possible to read the advisory at xenbits.xenproject.org. This vulnerability is known as CVE-2026-62424 since 07/14/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/02/2026).

The vulnerability scanner Nessus provides a plugin with the ID 331597 (Fedora 44 : xen (2026-bf1da84dfc)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at CNNVD (CNNVD-2026-97852465), Tenable (331597) and CERT Bund (WID-SEC-2026-2568). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Open Source Xen

Productinfo

Type

• Virtualization Software

Vendor

• Xen

Name

• libfsimage

License

• open-source

CPE 2.3info

• 🔒

CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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