# CVE-2026-89528: svcrdma: Reject Read lists that exceed the page budget

> A remote attacker can cause a kernel crash by sending crafted RDMA Read requests that bypass page budget checks, leading to a NULL pointer dereference.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-100166, BELL-CVE-2026-89528, DEBIAN-CVE-2026-89528, GHSA-4rjj-pgm8-m2r9, UBUNTU-CVE-2026-89528

## What is CVE-2026-89528?

CVE-2026-89528 is a high-severity vulnerability in Linux, published on 11 Sep 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:

svcrdma: Reject Read lists that exceed the page budget

Individual Read segment lengths are validated at decode time, but
nothing prevents a requester from sending multiple segments whose
cumulative length exceeds the rq_pages array budget. When one
segment fills the page array exactly, the runtime guard in
svc_rdma_build_read_segment() is bypassed because len reaches zero.
A subsequent segment then accesses the NULL sentinel slot at
rq_pages[rq_maxpages], resulting in a NULL pointer dereference during
DMA mapping.

Accumulate pages across all Read segments and reject the message at
decode time when the total would overflow the page budget.

## Which versions are affected by CVE-2026-89528?


## How do I fix CVE-2026-89528?

Apply the vendor's patch.

## Is CVE-2026-89528 being exploited?

There is no known exploitation of CVE-2026-89528 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89528 and fix it if it is affected.

What it is: CVE-2026-89528 is a high-severity vulnerability in Linux, published on 11 Sep 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-2026-89528 in the wild and no public exploit code.

Affected product: Linux. 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-2026-89528/ (Markdown: https://insights.sbomify.com/CVE-2026-89528/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89528
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89528
- OSV: https://osv.dev/vulnerability/CVE-2026-89528

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89528/
Summaries are generated and may contain mistakes; the official description above is the record.