# CVE-2023-5981: Gnutls: timing side-channel in the rsa-psk authentication

Status: published. Published: 2023-11-28. Updated: 2026-11-05.

A vulnerability was found that the response times to malformed ciphertexts in RSA-PSK ClientKeyExchange differ from response times of ciphertexts with correct PKCS#1 v1.5 padding.

## Remediation

- workaround: To address the issue found upgrade to GnuTLS 3.8.2 or later versions. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 8 (gnutls): ≥ 0:3.6.16-8.el8_9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support (gnutls): ≥ 0:3.6.16-5.el8_6.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Extended Update Support (gnutls): ≥ 0:3.6.16-7.el8_8.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (gnutls): ≥ 0:3.7.6-23.el9_3.3; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Extended Update Support (gnutls): ≥ 0:3.7.6-21.el9_2.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/cephcsi-rhel9): ≥ v4.15.0-37; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/mcg-core-rhel9): ≥ v4.15.0-68; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/mcg-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/mcg-rhel9-operator): ≥ v4.15.0-39; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/ocs-client-console-rhel9): ≥ v4.15.0-58; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/ocs-client-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/ocs-client-rhel9-operator): ≥ v4.15.0-13; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/ocs-metrics-exporter-rhel9): ≥ v4.15.0-81; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/ocs-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/ocs-rhel9-operator): ≥ v4.15.0-79; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-cli-rhel9): ≥ v4.15.0-22; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-console-rhel9): ≥ v4.15.0-57; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-cosi-sidecar-rhel9): ≥ v4.15.0-6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-csi-addons-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-csi-addons-rhel9-operator): ≥ v4.15.0-15; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-csi-addons-sidecar-rhel9): ≥ v4.15.0-15; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-multicluster-console-rhel9): ≥ v4.15.0-54; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-multicluster-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-multicluster-rhel9-operator): ≥ v4.15.0-10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-must-gather-rhel9): ≥ v4.15.0-26; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odf-rhel9-operator): ≥ v4.15.0-19; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odr-cluster-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odr-hub-operator-bundle): ≥ v4.15.0-158; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/odr-rhel9-operator): ≥ v4.15.0-21; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHODF-4.15-RHEL-9 (odf4/rook-ceph-rhel9-operator): ≥ v4.15.0-103; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/cluster-logging-operator-bundle): ≥ v5.8.6-22; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/cluster-logging-rhel9-operator): ≥ v5.8.6-11; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/elasticsearch6-rhel9): ≥ v6.8.1-407; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/elasticsearch-operator-bundle): ≥ v5.8.6-19; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/elasticsearch-proxy-rhel9): ≥ v1.0.0-479; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/elasticsearch-rhel9-operator): ≥ v5.8.6-7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/eventrouter-rhel9): ≥ v0.4.0-247; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/fluentd-rhel9): ≥ v5.8.6-5; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/log-file-metric-exporter-rhel9): ≥ v1.1.0-227; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/logging-curator5-rhel9): ≥ v5.8.1-470; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/logging-loki-rhel9): ≥ v2.9.6-14; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/logging-view-plugin-rhel9): ≥ v5.8.6-2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/loki-operator-bundle): ≥ v5.8.6-24; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/loki-rhel9-operator): ≥ v5.8.6-10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/lokistack-gateway-rhel9): ≥ v0.1.0-525; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/opa-openshift-rhel9): ≥ v0.1.0-224; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHOL-5.8-RHEL-9 (openshift-logging/vector-rhel9): ≥ v0.28.1-56; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (gnutls): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (gnutls): Version range not reported. Source: CNA: redhat
- Siemens / SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIPLUS S7-1500 CPU 1518-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP

## Severity and prioritization

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 1.27% as of 2026-11-04; percentile 69.85%

- SSVC: Not available

- Weaknesses: CWE-208

## Exploit evidence

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

## References

- https://access.redhat.com/errata/RHSA-2024:0155 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:0319 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:0399 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:0451 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:0533 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:1383 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:2094 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-5981 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2248445 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gnutls.org/security-new.html#GNUTLS-SA-2023-10-23 (CNA: redhat)

- http://www.openwall.com/lists/oss-security/2024/01/19/3 (ADP: CVE; x_transferred)

- https://access.redhat.com/errata/RHSA-2024:0155 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:0319 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:0399 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:0451 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:0533 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:1383 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2094 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-5981 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2248445 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://gnutls.org/security-new.html#GNUTLS-SA-2023-10-23 (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7ZEIOLORQ7N6WRPFXZSYDL2MC4LP7VFV/ (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GNXKVR5YNUEBNHAHM5GSYKBZX4W2HMN2/ (ADP: CVE; x_transferred)

- https://lists.debian.org/debian-lts-announce/2023/11/msg00016.html (ADP: CVE)

- https://cert-portal.siemens.com/productcert/html/ssa-398330.html (ADP: siemens-SADP)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-5981; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-5981; retrieved 2026-11-05; source updated Not reported

Revision: 4d968a858426e6fd9aafdfac229d84511bda18e494fc2dc2d357f74c3db40beb

Canonical: https://y2.dev/cve/CVE-2023-5981

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