Look up another CVE · open CVE-2026-92510 in the interactive tracker
CVE-2026-92510
RDMA/core: Fix potential use after free in ib_destroy_srq_user()
Published 2026-09-17 (31 days ago) by the Linux kernel CNA. Subsystem drivers/infiniband. Debian urgency: not yet assigned.
What to do, per Debian release
Debian's own status for CVE-2026-92510 in every release this site tracks, and what each one means in practice. Every status below is the one the Debian Security Team publishes for this CVE. source
| Release | Status | Version | What this means |
|---|---|---|---|
| Debian 12bookworm | fixedDLA-4841-1 · 2026-10-17 · text | 6.1.190-1 | Update the kernel and reboot. DLA-4841-1 shipped the fix on 2026-10-17, in 6.1.190-1. A running kernel keeps the old code until the machine restarts. |
| Debian 13trixie | fixedDSA-6528-1 · 2026-09-29 · text | 6.12.111-1 | Update the kernel and reboot. DSA-6528-1 shipped the fix on 2026-09-29, in 6.12.111-1. A running kernel keeps the old code until the machine restarts. |
| Debian 14forky | fixed | 7.2.6-1 | Update the kernel and reboot. Fixed in 7.2.6-1. A running kernel keeps the old code until the machine restarts. |
| Debian unstablesid | fixed | 7.2.6-1 | Update the kernel and reboot. Fixed in 7.2.6-1. A running kernel keeps the old code until the machine restarts. |
| Debian 12bookworm · linux-6.12 | fixedDLA-4817-1 · 2026-10-04 · text | 6.12.111-1~deb12u1 | Update the kernel and reboot. DLA-4817-1 shipped the fix on 2026-10-04, in 6.12.111-1~deb12u1. A running kernel keeps the old code until the machine restarts. |
The vulnerability
What the bug is
When accessing a SRQ via the netlink path the only synchronization mechanism for the said SRQ is rdma_restrack_get(). Currently, rdma_restrack_del() is invoked at the end of ib_destroy_srq_user(), which is too late, since by that point vendor-specific resources associated with the SRQ might already be freed. This can leave a short window where the SRQ remains accessible through restrack, leading to a potential use-after-free. Fix this by moving the rdma_restrack_begin_del() call to the start of ib_destroy_srq_user(), ensuring that the SRQ is removed from restrack before its internal resources are released. This guarantees that no new users hold references to a SRQ that is in the process of destruction. In addition, this change preserves the intended inverted order between create and destroy routines: resources are added to restrack at the end of successful creation, and hence shall be removed from the restrack first thing during the destruction flow, which keeps the lifecycle management consistent and predictable.
Where it lives
The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.
drivers/infiniband/core/verbs.c
- What this is
- INFINIBAND SUBSYSTEMMAINTAINERS section matched on drivers/infiniband/ · linux-rdma@vger.kernel.org · Supported
- Kernel module
- ib_core
Check it on the machine
grep -w CONFIG_INFINIBAND /boot/config-$(uname -r)Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.
lsmod | grep -w ib_corePrints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.
Show whether Debian builds this, per release
Debian builds this as a loadable module. Every release below compiles it as a module on every flavour, so whether the code is in the running kernel depends on whether that module is loaded.
- bookworm, trixie, forky, sid, bookworm · linux-6.12m
- m
- a loadable module on every flavour - check lsmod, can be blacklisted
- Build switch
- CONFIG_INFINIBAND
From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages
Signals
- Published
- 2026-09-17 (31 days ago)source
- CVSS
- 7.8 high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsource recompute it - Attack vector
- local (AV:L)source
- EPSS
- 0.13%, higher than 2.0% of all CVEssource
- CISA KEV
- not listedthe KEV catalogue
- Debian urgency
- not yet assignedsource
- Subsystem
- drivers/infiniband
Upstream fixes
The versions the CNA records as introducing and fixing this, and the commit for each. source
| Introduced | Fixed in | Commit |
|---|---|---|
| 5.13 | 6.1.188 | a5bfd9fe05d5 |
| 5.13 | 6.6.157 | d3d0eabe6e39 |
| 5.13 | 6.12.110 | 9c7043835290 |
| 5.13 | 6.18.52 | bedd7dee7258 |
| 5.13 | 7.2.6 | 95c992c869df |
| 5.13 | 7.3 | 88244ecc71cc |
Debian advisories
| Advisory | Date | Shipped to | Debian |
|---|---|---|---|
| DLA-4841-1 | 2026-10-17 | bookworm 6.1.190-1 | tracker |
| DLA-4817-1 | 2026-10-04 | bookworm 6.12.111-1~deb12u1 | tracker |
| DSA-6528-1 | 2026-09-29 | trixie 6.12.111-1 | tracker |
Why the CNA scored it this way
Quoted from the kernel CNA's own scoring file, word for word. A highlighted metric carries the most severe value CVSS v3.1 defines for it, which is what pushes the score up. source
- AV:LAttack vector, local
- Reached by a local write/ioctl on /dev/infiniband/uverbsN (IB_USER_VERBS_CMD_DESTROY_SRQ or UVERBS_METHOD_SRQ_DESTROY → uverbs_free_srq → ib_destroy_srq_user) raced with NETLINK_RDMA RDMA_NLDEV_CMD_RES_SRQ_GET; incoming RoCE/IB packets never invoke destroy_srq or fill_res_srq_entry.
- AC:LAttack complexity, low
- The attacker controls both sides: one thread DESTROY_SRQs the handle while another issues RDMA_NLDEV_CMD_RES_SRQ_GET so nldev_res_get_srq_doit → rdma_restrack_get_byid still finds the SRQ during ops.destroy_srq (e.g. hns_roce_destroy_srq's mailbox and wait_for_completion); no uninfluenced victim state is required.
- PR:LPrivileges required, low
- ib_uverbs_open() has no capable() check and uverbs_devnode() creates /dev/infiniband/uverbs* mode 0666, and RDMA_NLDEV_CMD_RES_SRQ_GET is registered without RDMA_NL_ADMIN_PERM, so an unprivileged local user on a host with an RDMA device can create an SRQ and dump it via nldev.
- UI:NUser interaction, none
- The attacker opens uverbs, creates the SRQ, and races DESTROY_SRQ with their own NETLINK_RDMA RES_SRQ_GET; no other user must mount, click, or otherwise act.
- S:UScope, unchanged
- The use-after-free is of the host-kernel ib_srq and its vendor SRQ resources inside ib_core; it does not escape a VM, bypass an IOMMU, or otherwise leave the kernel's authority.
- C:HConfidentiality impact, high
- After ops.destroy_srq frees vendor state (hns free_srqc/free_srq_buf, rxe_srq_cleanup→rxe_queue_cleanup, bnxt_qplib_destroy_srq kfree(swq)), the SRQ is still in restrack so fill_res_srq_entry/fill_res_srq_entry_raw (hns query_srqc, bnxt_qplib_read_context) read the freed object, a UAF disclosure primitive.
- I:HIntegrity impact, high
- The same UAF leaves vendor SRQ allocations (bnxt swq, siw recvq, rxe queue, mlx5 umem) freed while nldev still holds the restrack kref in fill_res_srq_entry, so heap reuse of those objects yields a write/control-flow primitive.
- A:HAvailability impact, high
- fill_res_srq_entry walking an SRQ whose vendor buffers were already released by destroy_srq (kfree/vfree of swq, recvq, or rxe queue) can oops the kernel, so availability impact is high even without a full exploit.