CVE-2026-123876

Podman: containers-common: containers-common: default seccomp af_vsock/netlink_audit deny rules bypassable via 32-bit truncation

Published Nov 6, 2026 CVSS 3.1 · 4.4 Medium EPSS < 1% KEV · Not listed
Description
A flaw was found in the default seccomp profile used by Podman via containers-common. Deny rules for AF_VSOCK and NETLINK_AUDIT compared socket arguments with unmasked 64-bit equality. Because the kernel truncates those int arguments to 32 bits, setting upper bits can bypass the deny rules.

Remediation

Vendor Workaround

Enforcing SELinux may still deny vsock; do not rely on the unfixed seccomp denies; ship SCMP_CMP_MASKED_EQ profile updates.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Containers
Containers podman
Red Hat
Red Hat enterprise Linux
Redhat hardened Images
Redhat openshift Container Platform
Vendors & Products Containers
Containers podman
Red Hat
Red Hat enterprise Linux
Redhat hardened Images
Redhat openshift Container Platform
Type Values Removed Values Added
Description A flaw was found in the default seccomp profile used by Podman via containers-common. Deny rules for AF_VSOCK and NETLINK_AUDIT compared socket arguments with unmasked 64-bit equality. Because the kernel truncates those int arguments to 32 bits, setting upper bits can bypass the deny rules.
Title Podman: containers-common: containers-common: default seccomp af_vsock/netlink_audit deny rules bypassable via 32-bit truncation
First Time appeared Redhat
Redhat enterprise Linux
Redhat hummingbird
Redhat openshift
Weaknesses CWE-184
CPEs cpe:/a:redhat:enterprise_linux:10
cpe:/a:redhat:enterprise_linux:8
cpe:/a:redhat:enterprise_linux:9
cpe:/a:redhat:hummingbird:1
cpe:/a:redhat:openshift:4
cpe:/a:redhat:openshift:5
Vendors & Products Redhat
Redhat enterprise Linux
Redhat hummingbird
Redhat openshift
References
Metrics cvssV3_1

{'score': 4.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}