buffer overruns in libfsimage iso9660 handling
Summary
| CVE | CVE-2026-62424 |
|---|---|
| State | PUBLISHED |
| Assigner | XEN |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-28 13:19:01 UTC |
| Updated | 2026-07-28 16:19:30 UTC |
| Description | [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. |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from ADP
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS: 0.002050000 probability, percentile 0.107340000 (date 2026-07-29)
Problem Types: CWE-130 | CWE-130 CWE-130 Improper Handling of Length Parameter Inconsistency
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
NoneUser Interaction
RequiredScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| xenbits.xenproject.org/xsa/advisory-497.html | [email protected] | xenbits.xenproject.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: This issue was discovered by Syed Abdul Khaliq of BugQore. (en)
Additional Advisory Data
Workarounds
CNA: XSA-443 added a mechanism to run pygrub de-privileged. Using this mode will mitigate the vulnerability. Ensuring that guests do not use the pygrub bootloader will avoid this vulnerability. For cases where the PV guest is known to be 64bit, and uses grub2 as a bootloader, pvgrub is a suitable alternative to pygrub. Running only HVM or PVH guests will avoid the vulnerability.
There are currently no legacy QID mappings associated with this CVE.