Affected: AlmaLinux:9: runc

The runC tool is a lightweight, portable implementation of the Open Container Format (OCF) that provides container runtime.

Security Fix(es):

* runc: container escape via 'masked path' abuse due to mount race conditions (CVE-2025-31133) * runc: container escape with malicious config due to /dev/console mount and related races (CVE-2025-52565) * runc: container escape and denial of service due to arbitrary write gadgets and procfs write redirects (CVE-2025-52881)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Affected: Alpaquita:25: runc, Alpaquita:stream: runc

runc is a CLI tool for spawning and running containers according to the OCI specification. Versions 1.0.0-rc3 through 1.2.7, 1.3.0-rc.1 through 1.3.2, and 1.4.0-rc.1 through 1.4.0-rc.2, due to insufficient checks when bind-mounting `/dev/pts/$n` to `/dev/console` inside the container, an attacker can trick runc into bind-mounting paths which would normally be made read-only or be masked onto a path that the attacker can write to. This attack is very similar in concept and application to CVE-2025-31133, except that it attacks a similar vulnerability in a different target (namely, the bind-mount of `/dev/pts/$n` to `/dev/console` as configured for all containers that allocate a console). This happens after `pivot_root(2)`, so this cannot be used to write to host files directly -- however, as with CVE-2025-31133, this can load to denial of service of the host or a container breakout by providing the attacker with a writable copy of `/proc/sysrq-trigger` or `/proc/sys/kernel/core_pattern` (respectively). This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.

Affected: Go: github.com/opencontainers/runc

### Impact ### This attack is very similar in concept and application to CVE-2025-31133, except that it attacks a similar vulnerability in a different target (namely, the bind-mount of `/dev/pts/$n` to `/dev/console` as configured for all containers that allocate a console).

In runc version 1.0.0-rc3 and later, due to insufficient checks when bind-mounting `/dev/pts/$n` to `/dev/console` inside the container, an attacker can trick runc into bind-mounting paths which would normally be made read-only or be masked onto a path that the attacker can write to. This happens after `pivot_root(2)`, so this cannot be used to write to host files directly -- however, as with CVE-2025-31133, this can load to denial of service of the host or a container breakout by providing the attacker with a writable copy of `/proc/sysrq-trigger` or `/proc/sys/kernel/core_pattern` (respectively).

The reason that the attacker can gain write access to these files is because the `/dev/console` bind-mount happens before `maskedPaths` and `readonlyPaths` are applied.

#### Additional Findings #### While investigating this issue, runc discovered some other theoretical issues that may or may not be exploitable, as well as taking the opportunity to fix some fairly well-known issues related to consoles.

##### Issue 1: Problematic Usage of `os.Create` ##### Go provides an `os.Create` function for creating files, which older code in runc (dating back to the original `libcontainer` from the early 2010s) had a…

Affected: openEuler:20.03-LTS-SP4: runc, openEuler:22.03-LTS-SP3: runc, openEuler:22.03-LTS-SP4: runc, openEuler:24.03-LTS: runc, openEuler:24.03-LTS-SP1: runc, openEuler:24.03-LTS-SP2: runc

runc is a CLI tool for spawning and running containers according to the OCI specification. Security Fix(es):

runc is a CLI tool for spawning and running containers according to the OCI specification. In versions 1.2.7 and below, 1.3.0-rc.1 through 1.3.1, 1.4.0-rc.1 and 1.4.0-rc.2 files, runc would not perform sufficient verification that the source of the bind-mount (i.e., the container's /dev/null) was actually a real /dev/null inode when using the container's /dev/null to mask. This exposes two methods of attack: an arbitrary mount gadget, leading to host information disclosure, host denial of service, container escape, or a bypassing of maskedPaths. This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.(CVE-2025-31133)

runc is a CLI tool for spawning and running containers according to the OCI specification. Versions 1.0.0-rc3 through 1.2.7, 1.3.0-rc.1 through 1.3.2, and 1.4.0-rc.1 through 1.4.0-rc.2, due to insufficient checks when bind-mounting `/dev/pts/$n` to `/dev/console` inside the container, an attacker can trick runc into bind-mounting paths which would normally be made read-only or be masked onto a path that the attacker can write to. This attack is very similar in concept and application to CVE-2025-31133, except that it attacks a similar vulnerability in a different target (namely, the bind-mount of `/dev/pts/$n` to `/dev/console` as configured for all containers that allocate a console). This happens after `pivot_root(2)`, so this cannot…

runc-1.3.3-1.1 on GA media

runc: container escape via 'masked path' abuse due to mount race conditions runc: container escape with malicious config due to /dev/console mount and related races

Security update for runc

Affected: Ubuntu:Pro:16.04:LTS: runc, Ubuntu:Pro:18.04:LTS: runc, Ubuntu:20.04:LTS: runc, Ubuntu:20.04:LTS: runc-app, Ubuntu:22.04:LTS: runc, Ubuntu:22.04:LTS: runc-app, Ubuntu:24.04:LTS: runc, Ubuntu:24.04:LTS: runc-app, Ubuntu:25.10: runc, Ubuntu:25.10: runc-app and 1 more

runc is a CLI tool for spawning and running containers according to the OCI specification. Versions 1.0.0-rc3 through 1.2.7, 1.3.0-rc.1 through 1.3.2, and 1.4.0-rc.1 through 1.4.0-rc.2, due to insufficient checks when bind-mounting `/dev/pts/$n` to `/dev/console` inside the container, an attacker can trick runc into bind-mounting paths which would normally be made read-only or be masked onto a path that the attacker can write to. This attack is very similar in concept and application to CVE-2025-31133, except that it attacks a similar vulnerability in a different target (namely, the bind-mount of `/dev/pts/$n` to `/dev/console` as configured for all containers that allocate a console). This happens after `pivot_root(2)`, so this cannot be used to write to host files directly -- however, as with CVE-2025-31133, this can load to denial of service of the host or a container breakout by providing the attacker with a writable copy of `/proc/sysrq-trigger` or `/proc/sys/kernel/core_pattern` (respectively). This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.

Ein lokaler Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux und Red Hat OpenShift ausnutzen, um Sicherheitsvorkehrungen zu umgehen und einen Denial of Service herbeizuführen.