# CVE-2026-46114: RDMA/rxe: Reject non-8-byte ATOMIC_WRITE payloads

> A remote attacker can leak kernel memory by sending malformed RDMA ATOMIC_WRITE requests with zero-length payloads, exposing sensitive kernel data.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 May 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-89115, BELL-CVE-2026-46114, DEBIAN-CVE-2026-46114, GHSA-pv35-9gqp-7q2c, ROOT-OS-UBUNTU-2404-CVE-2026-46114, UBUNTU-CVE-2026-46114

## What is CVE-2026-46114?

CVE-2026-46114 is a high-severity vulnerability in Linux kernel, published on 28 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

RDMA/rxe: Reject non-8-byte ATOMIC_WRITE payloads

atomic_write_reply() at drivers/infiniband/sw/rxe/rxe_resp.c
unconditionally dereferences 8 bytes at payload_addr(pkt):

    value = *(u64 *)payload_addr(pkt);

check_rkey() previously accepted an ATOMIC_WRITE request with pktlen ==
resid == 0 because the length validation only compared pktlen against
resid. A remote initiator that sets the RETH length to 0 therefore reaches
atomic_write_reply() with a zero-byte logical payload, and the responder
reads sizeof(u64) bytes from past the logical end of the packet into
skb->head tailroom, then writes those 8 bytes into the attacker's MR via
rxe_mr_do_atomic_write(). That is a remote disclosure of 4 bytes of kernel
tailroom per probe (the other 4 bytes are the packet's own trailing ICRC).

IBA oA19-28 defines ATOMIC_WRITE as exactly 8 bytes. Anything else is
protocol-invalid. Hoist a strict length check into check_rkey() so the
responder never reaches the unchecked dereference, and keep the existing
WRITE-family length logic for the normal RDMA WRITE path.

Reproduced on mainline with an unmodified rxe driver: a sustained
zero-length ATOMIC_WRITE probe repeatedly leaks adjacent skb head-buffer
bytes into the attacker's MR, including recognisable kernel strings and
partial kernel-direct-map pointer words.  With this patch applied the
responder rejects the PDU and the MR stays all-zero.

Weakness: CWE-476 (NULL Pointer Dereference), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-46114?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46114?

Apply the vendor's patch.

## Is CVE-2026-46114 being exploited?

There is no known exploitation of CVE-2026-46114 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-2026-46114 and fix it if it is affected.

What it is: CVE-2026-46114 is a high-severity vulnerability in Linux kernel, published on 28 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-46114 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-2026-46114/ (Markdown: https://insights.sbomify.com/CVE-2026-46114/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46114
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46114
- OSV: https://osv.dev/vulnerability/CVE-2026-46114

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46114/
Summaries are generated and may contain mistakes; the official description above is the record.