---
id: "CVE-2026-85231"
kind: "vulnerability"
aliases: ["CVE-2026-85231"]
title: "libtirpc: oversized RPCSEC_GSS requests exhaust memory and crash services"
severity: "medium"
cvss: 6.5
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "kerberos", "linux", "nfs", "self-hosted"]
not_affected_if: ["no-rpc-services", "no-rpcsec-gss"]
published_at: "2026-10-16T19:17:44+00:00"
first_seen_at: "2026-10-23T21:57:14+00:00"
updated_at: "2026-10-25T03:57:45+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-85231", "first_seen_at": "2026-10-23T21:57:14+00:00"}]
---

# libtirpc: oversized RPCSEC_GSS requests exhaust memory and crash services

libtirpc, the RPC library used by many Linux and Unix services, does not bound memory allocation for oversized wrapped data in RPCSEC_GSS integrity or privacy requests. An authenticated remote attacker can exhaust system memory, making the RPC service unstable or terminating it.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed libtirpc version with `rpm -q libtirpc` or `dpkg -s libtirpc3`
- Check whether an RPC service uses RPCSEC_GSS with integrity or privacy, for example in `/etc/exports` or the NFS/gssd configuration
- unknown for the vulnerable version range

## Fix

- Update libtirpc to the patched version from your distribution's security advisory (version unknown from the sources)
- Restart affected RPC services after the update

## Timeline

- 2026-10-23T21:57:14+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-85231

## From the sources

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.

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