Xen libfsimage Rock Ridge extension input validation

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.9$0-$5k3.37-

Summaryinfo

A vulnerability labeled as very critical has been found in Xen libfsimage. The affected element is an unknown function of the component Rock Ridge extension. The manipulation results in input validation. This vulnerability is reported as CVE-2026-62423. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Xen libfsimage (the affected version unknown). Affected is an unknown part of the component Rock Ridge extension. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

[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.

The advisory is available at xenbits.xenproject.org. This vulnerability is traded as CVE-2026-62423 since 07/14/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/28/2026).

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

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Productinfo

Type

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.9

VulDB Base Score: 9.9
VulDB Temp Score: 9.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/14/2026 CVE reserved
07/28/2026 +14 days Advisory disclosed
07/28/2026 +0 days VulDB entry created
07/28/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: xenbits.xenproject.org
Status: Confirmed

CVE: CVE-2026-62423 (🔒)
GCVE (CVE): GCVE-0-2026-62423
GCVE (VulDB): GCVE-100-383862

Entryinfo

Created: 07/28/2026 15:33
Changes: 07/28/2026 15:33 (52)
Complete: 🔍
Cache ID: 216::103

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