# CVE-2026-85231: Libtirpc: libtirpc: denial of service via unbounded memory allocation during rpcsec_gss decoding

> An authenticated attacker can cause denial of service in RPC services using RPCSEC_GSS by triggering unbounded memory allocation via oversized requests.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Oct 2026
- **Updated:** 16 Oct 2026
- **Also known as:** BELL-CVE-2026-85231, DEBIAN-CVE-2026-85231, ECHO-a4aa-20f1-90de, GHSA-xhf3-w45r-cmh3, UBUNTU-CVE-2026-85231

## What is CVE-2026-85231?

CVE-2026-85231 is a medium-severity denial of service vulnerability in Red Hat Enterprise Linux 10, published on 16 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A flaw was found in libtirpc. An authenticated remote attacker could exploit this vulnerability by sending oversized wrapped data requests to an RPC (Remote Procedure Call) service configured with RPCSEC_GSS (Remote Procedure Call Security-Generic Security Service) integrity or privacy. This can lead to unbounded memory allocation, resulting in a Denial of Service (DoS) by exhausting system resources and causing the service to become unstable or terminate.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-85231?


## How do I fix CVE-2026-85231?

Apply the vendor's patch.

## Is CVE-2026-85231 being exploited?

There is no known exploitation of CVE-2026-85231 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-85231 and fix it if it is affected.

What it is: CVE-2026-85231 is a medium-severity denial of service vulnerability in Red Hat Enterprise Linux 10, published on 16 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-85231 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 10. 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-2026-85231/ (Markdown: https://insights.sbomify.com/CVE-2026-85231/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-85231
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-85231
- OSV: https://osv.dev/vulnerability/CVE-2026-85231

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-85231/
Summaries are generated and may contain mistakes; the official description above is the record.