# CVE-2026-3832: GnuTLS certificate revocation bypass in OCSP response handling

Source: https://junglewise.ai/threats/cve-2026-3832-gnutls-certificate-revocation-bypass-in-ocsp-response-handling  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-30. Updated: 2026-06-01  
License: CC BY 4.0 with a link back

CVE-2026-3832 · Severity: low · CVSS 3.7 · Published 2026-04-30

GnuTLS is a widely used security library that helps applications establish encrypted connections. A flaw was found where the library incorrectly processes certificate status updates (OCSP), which are used to check if a security certificate has been cancelled or revoked. An attacker could exploit this to make a client accept a revoked or untrustworthy certificate, potentially allowing them to impersonate a legitimate service or intercept encrypted communications.

## Quick answers

**Is CVE-2026-3832 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-3832 being exploited in the wild.

**How severe is CVE-2026-3832?** Low severity, with a CVSS score of 3.7, published 30 April 2026.

**Which products and versions are affected?** GNU GnuTLS 3.8.13-1.hum1, 3.8.10-4.el10_2; Red Hat Enterprise Linux 6.0, 7.0, 8.0, 9.0, 10.0, 10.2; Red Hat OpenShift Container Platform 4.0.

**Is there a fix for CVE-2026-3832?** A patch was published on 2026-05-02: Red Hat released security updates (RHSA-2026:13274) Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-3832 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-3832?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A logic error exists in GnuTLS within the 'check_ocsp_response' function in 'lib/cert-session.c'. While the library correctly identifies the matching record index for a certificate using 'gnutls_ocsp_resp_check_crt', it incorrectly defaults to reading the certificate status from index 0 via 'gnutls_ocsp_resp_get_single' regardless of the actual match. A remote attacker can exploit this by providing a multi-record OCSP response where the first record indicates a 'good' status for an unrelated certificate, while the actual record for the server's revoked certificate appears later in the response. This results in the client incorrectly accepting a revoked certificate. Patches have been released by Red Hat for various Enterprise Linux versions.

## Affected products

- GNU GnuTLS 3.8.13-1.hum1, 3.8.10-4.el10_2
- Red Hat Enterprise Linux 6.0, 7.0, 8.0, 9.0, 10.0, 10.2
- Red Hat OpenShift Container Platform 4.0

## Timeline

- 2026-03-09: disclosed: Bug reported to Red Hat Bugzilla
- 2026-04-30: advisory: Initial CVE publication
- 2026-05-02: patched: Red Hat released security updates (RHSA-2026:13274)

## References

- [https://access.redhat.com/errata/RHSA-2026:13274](https://access.redhat.com/errata/RHSA-2026:13274)
- [https://access.redhat.com/errata/RHSA-2026:20613](https://access.redhat.com/errata/RHSA-2026:20613)
- [https://access.redhat.com/security/cve/CVE-2026-3832](https://access.redhat.com/security/cve/CVE-2026-3832)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2445762](https://bugzilla.redhat.com/show_bug.cgi?id=2445762)
- [https://gitlab.com/gnutls/gnutls/-/issues/1801](https://gitlab.com/gnutls/gnutls/-/issues/1801)