CVE-2026-74395
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix devx subscribe-event unwind NULL dereference MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT() links event_sub into sub_list before initializing the fields used by the shared error path. If eventfd_ctx_fdget() then fails, the unwind path dereferences event_sub->ev_file in uverbs_uobject_put() and calls subscribe_event_xa_dealloc() with an unset xa_key_level1. subscribe_event_xa_alloc() creates the XA entry exactly once for a given key_level1, on the first occurrence of that key. The unwind path must therefore call subscribe_event_xa_dealloc() exactly once for it as well. Enforce that by adding devx_key_in_sub_list() and calling subscribe_event_xa_dealloc() only when the last matching pending entry is being cleaned up.
Executive briefing
The source record describes: In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix devx subscribe-event unwind NULL dereference MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT() links event_sub into sub_list before initializing the fields used by the shared error path. If eventfd_ctx_fdget() then fails, the unwind path dereferences event_sub->ev_file in uverbs_uobject_put() and calls subscribe_event_xa_dealloc() with an unset xa_key_level1. subscribe_event_xa_alloc() creates the XA entry exactly once for a given key_level1, on the first occurrence of that key. The unwind path must therefore call subscribe_event_xa_dealloc() exactly once for it as well. Enforce that by adding devx_key_in_sub_list() and calling subscribe_event_xa_dealloc() only when the last matching pending entry is being cleaned up. 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: Low 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/1025dc2f7ba29b04b8687790fa91f9cd1a53141e REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/43f8f7946814c8e5f464518246fdbc69b6e32326 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/6e15b770461eeaa0ff73934922cb670a6a9db04e REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/78b9589fda266c71f0f9d0c858d4fa7381a890a5 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/7921821fc2b19c01588311f6e7468ae5b68b1f61 REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/9be9aca28424228586fe9211c373ebdb826ebb6c REFERENCE 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/f345e744b6b087188cde2377da5cbe9713b61353 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 vendor advisory or patch reference was identified in the supplied CVE references.
- No CVSS vector is currently available in the source record.
- No CWE classification is currently available.
Last enrichment: 2026-11-07T16:42:46+00:00 · Source last modified: 2026-11-06T17:19:47.527