---
id: CVE-2023-0361
title: >-
  A timing side-channel in the handling of RSA ClientKeyExchange messages was
  discovered in GnuTLS
summary: >-
  A timing side-channel in the handling of RSA ClientKeyExchange messages was
  discovered in GnuTLS. This side-channel can be sufficient to recover the key
  encrypted in the RSA ciphertext across a network in a Bleichenbacher style
  attack. T…
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-203
  - CWE-203
vendor: gnu
product: gnutls
affected:
  - gnutls = 3.6.8-11.el8_2
  - enterprise_linux = 8.0
  - enterprise_linux = 9.0
  - debian_linux = 10.0
  - fedora = 36
  - fedora = 37
  - fedora = 38
  - active_iq_unified_manager
  - converged_systems_advisor_agent
  - ontap_select_deploy_administration_utility
published: '2023-02-15'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T20:17:23.223'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-0361'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2023-0361'
    label: secalert@redhat.com
  - url: 'https://github.com/tlsfuzzer/tlsfuzzer/pull/679'
    label: secalert@redhat.com
  - url: 'https://gitlab.com/gnutls/gnutls/-/issues/1050'
    label: secalert@redhat.com
  - url: 'https://lists.debian.org/debian-lts-announce/2023/02/msg00015.html'
    label: secalert@redhat.com
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFIA3X4IZ3CW7SRQ2UHNHNPMRIAWF2FI/
    label: secalert@redhat.com
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS4KVDOG6QTALWHC2QE4Y7VPDRMLTRWQ/
    label: secalert@redhat.com
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z634YBXAJ5VLDI62IOPBVP5K6YFHAWCY/
    label: secalert@redhat.com
  - url: 'https://security.netapp.com/advisory/ntap-20230324-0005/'
    label: secalert@redhat.com
  - url: 'https://security.netapp.com/advisory/ntap-20230725-0005/'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2023-0361'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/tlsfuzzer/tlsfuzzer/pull/679'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://gitlab.com/gnutls/gnutls/-/issues/1050'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2023/02/msg00015.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFIA3X4IZ3CW7SRQ2UHNHNPMRIAWF2FI/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS4KVDOG6QTALWHC2QE4Y7VPDRMLTRWQ/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z634YBXAJ5VLDI62IOPBVP5K6YFHAWCY/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20230324-0005/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20230725-0005/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-806742.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
epss: 0.01415
epssPercentile: 0.7221
ingestedAt: '2026-10-14T20:53:12.257Z'
---

## Overview

A timing side-channel in the handling of RSA ClientKeyExchange messages was discovered in GnuTLS. This side-channel can be sufficient to recover the key encrypted in the RSA ciphertext across a network in a Bleichenbacher style attack. To achieve a successful decryption the attacker would need to send a large amount of specially crafted messages to the vulnerable server. By recovering the secret from the ClientKeyExchange message, the attacker would be able to decrypt the application data exchanged over that connection.

## Affected

- `gnutls = 3.6.8-11.el8_2`
- `enterprise_linux = 8.0`
- `enterprise_linux = 9.0`
- `debian_linux = 10.0`
- `fedora = 36`
- `fedora = 37`
- `fedora = 38`
- `active_iq_unified_manager`
- `converged_systems_advisor_agent`
- `ontap_select_deploy_administration_utility`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.