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

Published Nov 7, 2023
·
Updated

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.

Other sources

GNU GnuTLS could allow a remote attacker to obtain sensitive information, caused by a timing sidechannel issue during RSA-PSK key exchange. By sending a specially crafted request, an attacker could exploit this vulnerability to obtain sensitive information, and use this information to launch further attacks against the affected system.

— IBM

gnutls: timing side-channel in the RSA-PSK authentication https://gitlab.com/gnutls/gnutls/-/issues/1511

— Red Hat

Affected Software

27 affected componentsFixes available
redhat/GnuTLS<3.8.2
3.8.2
ubuntu/gnutls28<3.5.18-1ubuntu1.6+
3.5.18-1ubuntu1.6+
ubuntu/gnutls28<3.6.13-2ubuntu1.9
3.6.13-2ubuntu1.9
ubuntu/gnutls28<3.7.3-4ubuntu1.3
3.7.3-4ubuntu1.3
ubuntu/gnutls28<3.7.8-5ubuntu1.1
3.7.8-5ubuntu1.1
ubuntu/gnutls28<3.8.1-4ubuntu1.1
3.8.1-4ubuntu1.1
ubuntu/gnutls28<3.8.2
3.8.2
debian/gnutls28<=3.6.7-4+deb10u8, <=3.7.1-5+deb11u3
3.6.7-4+deb10u123.7.1-5+deb11u43.7.9-2+deb12u23.8.5-2
GNU GnuTLS=1.5.0
redhat Linux=8.0
redhat Linux=9.0
Fedoraproject Fedora=37
Fedoraproject Fedora=38
IBM QRadar Network Packet Capture<=7.5.0 - 7.5.0 Update Package 7
Debian Debian Linux=10.0
GNU GnuTLS<3.8.2
F5 BIG-IP Next>=20.0.1<=20.0.2
20.1.0
F5 BIG-IP Next Central Manager>=20.0.1<=20.0.2
20.1.0
F5 BIG-IP Next SPK>=1.5.0<=1.9.1
F5 BIG-IP Next CNF>=1.1.0<=1.3.0
F5 BIG-IP>=17.1.0<=17.5.1
17.5.1.317.1.3
F5 BIG-IP>=16.1.0<=16.1.6
F5 BIG-IP>=15.1.0<=15.1.10
F5 BIG-IQ Centralized Management>=8.0.0<=8.4.0
F5 F5OS-A>=1.8.0<=1.8.3, =1.7.0, >=1.5.0<=1.5.4, =1.4.0, >=1.3.0<=1.3.2
1.8.4
F5 F5OS-C>=1.8.0<=1.8.2, >=1.6.0<=1.6.4, >=1.5.0<=1.5.1
F5 Traffix SDC>=5.1.0<=5.2.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/GnuTLS to a version that resolves this vulnerability.

    Fixed in 3.8.2
  2. Upgrade

    Upgrade ubuntu/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.5.18-1ubuntu1.6+
  3. Upgrade

    Upgrade ubuntu/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.6.13-2ubuntu1.9
  4. Upgrade

    Upgrade ubuntu/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.7.3-4ubuntu1.3
  5. Upgrade

    Upgrade ubuntu/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.7.8-5ubuntu1.1
  6. Upgrade

    Upgrade ubuntu/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.8.1-4ubuntu1.1
  7. Upgrade

    Upgrade ubuntu/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.8.2
  8. Upgrade

    Upgrade debian/gnutls28 to a version that resolves this vulnerability.

    Fixed in 3.6.7-4+deb10u12Fixed in 3.7.1-5+deb11u4Fixed in 3.7.9-2+deb12u2Fixed in 3.8.5-2
  9. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 20.1.0
  10. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 17.5.1.317.1.3
  11. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 1.8.4

Event History

Nov 17, 2023
CVE Published
via Ubuntu·12:00 AM
Nov 28, 2023
CVE Published
via MITRE·11:49 AM
Data Sourced
via MITRE·11:49 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·12:15 PM
DescriptionSeverityWeaknessAffected Software
Feb 17, 2024
Data Sourced
via Launchpad·12:52 PM
Description
Feb 21, 2024
Advisory Published
via F5·02:28 AM
Data Sourced
via F5·02:28 AM
DescriptionSeverityWeaknessAffected Software
Jul 23, 2024
Data Sourced
via IBM·12:00 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2023-5981?

CVE-2023-5981 is a vulnerability found in the RSA-PSK key exchange in GnuTLS, where response times to malformed ciphertexts differ from response times of ciphertexts with correct PKCS#1 v1.5 padding.

2

What is the severity of CVE-2023-5981?

The severity of CVE-2023-5981 is high with a CVSS severity score of 7.4.

3

Which software versions are affected by CVE-2023-5981?

GnuTLS versions up to and excluding 3.8.2, Gnu Gnutls version 1.5.0, Redhat Linux versions 8.0 and 9.0, and Fedora versions 37 and 38 are affected by CVE-2023-5981.

4

How can I fix CVE-2023-5981?

To fix CVE-2023-5981, upgrade GnuTLS to version 3.8.3 or higher.

5

Where can I find more information about CVE-2023-5981?

More information about CVE-2023-5981 can be found on the Red Hat Security Advisory and Bugzilla pages, as well as the GnuTLS GitLab issue.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203