# CVE-2026-46176: RDMA/mlx5: Fix error path fall-through in mlx5_ib_dev_res_srq_init()

> A use-after-free vulnerability in the Linux kernel RDMA driver allows attackers to cause denial of service or potentially execute code via crafted network traffic.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 May 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-88836, BELL-CVE-2026-46176, DEBIAN-CVE-2026-46176, GHSA-r8g9-gm9p-ff4h, ROOT-OS-UBUNTU-2404-CVE-2026-46176, UBUNTU-CVE-2026-46176

## What is CVE-2026-46176?

CVE-2026-46176 is a high-severity use after free vulnerability in Linux kernel, published on 28 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

RDMA/mlx5: Fix error path fall-through in mlx5_ib_dev_res_srq_init()

mlx5_ib_dev_res_srq_init() allocates two SRQs, s0 and s1. When
ib_create_srq() fails for s1, the error branch destroys s0 but falls
through and unconditionally assigns the freed s0 and the ERR_PTR s1 to
devr->s0 and devr->s1.

This leads to several problems: the lock-free fast path checks
"if (devr->s1) return 0;" and treats the ERR_PTR as already initialised;
users in mlx5_ib_create_qp() dereference the freed SRQ or ERR_PTR via
to_msrq(devr->s0)->msrq.srqn; and mlx5_ib_dev_res_cleanup() dereferences
the ERR_PTR and double-frees s0 on teardown.

Fix by adding the same `goto unlock` in the s1 failure path.

Weakness: CWE-825 (Expired Pointer Dereference)

## Which versions are affected by CVE-2026-46176?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46176?

Apply the vendor's patch.

## Is CVE-2026-46176 being exploited?

There is no known exploitation of CVE-2026-46176 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-46176 and fix it if it is affected.

What it is: CVE-2026-46176 is a high-severity use after free vulnerability in Linux kernel, published on 28 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-46176 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-46176/ (Markdown: https://insights.sbomify.com/CVE-2026-46176/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46176
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46176
- OSV: https://osv.dev/vulnerability/CVE-2026-46176

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46176/
Summaries are generated and may contain mistakes; the official description above is the record.