CVE-2026-99249
In the Linux kernel, the following vulnerability has been resolved: pid_namespace: make zap_pid_ns_processes() freezable When the init of a pid namespace exits, zap_pid_ns_processes() waits until all other pids in the namespace are freed. A tracer outside the namespace that does not reap its traced zombies keeps those pids allocated, so this wait has no upper bound, and while it lasts every suspend attempt fails: Freezing user space processes failed after 20.006 seconds (2 tasks refusing to freeze, wq_busy=0): Neither wait is freezable. The first loop sleeps in do_wait(), which returns -ERESTARTSYS on the freezer's fake signal; the loop then clears TIF_SIGPENDING and waits again without ever freezing. The final loop sleeps in TASK_INTERRUPTIBLE, and since nothing clears TIF_SIGPENDING there, schedule() returns immediately after the first freeze attempt and the task spins until the wait ends. Sleep in TASK_INTERRUPTIBLE | TASK_FREEZABLE in do_wait(), so that the freezer can freeze tasks waiting there directly, and in TASK_IDLE | TASK_FREEZABLE in the final loop, like coredump_task_exit() does. This was hit with Chromium-based browsers: crashpad ptrace-attaches the threads of a crashed renderer, which is a pid namespace init, and does not reap those killed during the dump.
Executive briefing
The source record describes: In the Linux kernel, the following vulnerability has been resolved: pid_namespace: make zap_pid_ns_processes() freezable When the init of a pid namespace exits, zap_pid_ns_processes() waits until all other pids in the namespace are freed. A tracer outside the namespace that does not reap its traced zombies keeps those pids allocated, so this wait has no upper bound, and while it lasts every suspend attempt fails: Freezing user space processes failed after 20.006 seconds (2 tasks refusing to freeze, wq_busy=0): Neither wait is freezable. The first loop sleeps in do_wait(), which returns -ERESTARTSYS on the freezer's fake signal; the loop then clears TIF_SIGPENDING and waits again without ever freezing. The final loop sleeps in TASK_INTERRUPTIBLE, and since nothing clears TIF_SIGPENDING there, schedule() returns immediately after the first freeze attempt and the task spins until the wait ends. Sleep in TASK_INTERRUPTIBLE | TASK_FREEZABLE in do_wait(), so that the freezer can freeze tasks waiting there directly, and in TASK_IDLE | TASK_FREEZABLE in the final loop, like coredump_task_exit() does. This was hit with Chromium-based browsers: crashpad ptrace-attaches the threads of a crashed renderer, which is a pid namespace init, and does not reap those killed during the dump. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Limited Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:
No CVSS vector is currently available in the source record.
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Affected products and versions
NVD has not supplied machine-readable vulnerable CPE product/version entries for this CVE. This is an information gap, not proof that no products are affected. Check the vendor advisory references below.
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://git.kernel.org/stable/c/064a6761d6f6ac55d090d3eaca649577ee736713 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/2e10b8a74f55b5aae33db105d3e2d3ae759c865a VENDOR 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/4b47107f1a80c809c80093e872bcaccdbae13db4 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/7deb5770840339fe88755bf27b92f74edc26ee87 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/81933038f5e273d17ed22792f906889393b204c5 VENDOR 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/e8dafad7de9ede813af2d48cc04b7c88fef16682 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Information gaps & confidence notes
These gaps indicate missing source data. CVE Watch does not fill them with guessed product, exploit or patch details.
- NVD does not currently provide machine-readable vulnerable CPE product/version entries for this record.
- No CVSS vector is currently available in the source record.
- No CWE classification is currently available.
Last enrichment: 2026-11-04T12:04:58+00:00 · Source last modified: 2026-11-03T12:17:31.460