Xen XAPI flaw allows security bypass
A vulnerability in Xen XAPI (unpatched by xsa498.patch) lets an attacker bypass security policy enforcement.
Sourcecert.ssi.gouv.fr — open the original
What to check
- Applies to
- The 1 CVE named below. Whether you run an affected version is not assessed: check the versions the source lists.
- Exploitation
- No exploitation in the wild and no public exploit is recorded for the CVEs named.
ANSSI-CERT-FR published an advisory covering CVE-2026-42491, a vulnerability in Xen's XAPI toolstack that allows an attacker to circumvent security policy controls. The issue affects XAPI master instances that have not applied the xsa498.patch fix released by the Xen Project.
The vendor advisory (XSA-498) was published on 14 July 2026 with corresponding patches. Administrators running affected Xen XAPI deployments should apply the official patch referenced in the Xen security bulletin as soon as possible. No evidence of active exploitation is mentioned in the advisory.
Mentioned in this report
Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-0884
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