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

Status: published. Published: 2026-10-16. Updated: 2026-11-06.

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.

## Remediation

- workaround: To reduce exposure, disable RPCSEC_GSS integrity or privacy modes on externally reachable RPC services where feasible. Implement strict request or transport record size limits in the embedding RPC service before wrapped blob decoding. Additionally, consider using process memory limits or supervision to contain single-process memory exhaustion. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (libtirpc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libtirpc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libtirpc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (libtirpc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libtirpc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Hardened Images (libtirpc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-8): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-9): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 5 (openshift/ose-rhel-coreos-9): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.30% as of 2026-11-05; percentile 22.49%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-770

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/security/cve/CVE-2026-85231 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2478512 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-85231; retrieved 2026-11-06; source updated 2026-11-06

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-85231; retrieved 2026-11-06; source updated Not reported

Revision: 19f024f476b4d4ab925c8651df987ff0ff4631346bf3d9d959a37006bc304342

Canonical: https://y2.dev/cve/CVE-2026-85231

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