CVE-2026-67693
An issue in gnutls v.3.8.13 allows an attacker to obtain sensitive information via failing to...
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
3.7
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
- Record
CVE-2026-67693- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-367
- Updated
- 2026-11-04
EUVDEUVD-2026-95206
3.7
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
- Record
EUVD-2026-95206- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-04
GitHub AdvisoriesGHSA-j75v-5pm7-3cg8
7.5
An issue in gnutls v.3.8.13 allows an attacker to obtain sensitive information via failing to...
An issue in gnutls v.3.8.13 allows an attacker to obtain sensitive information via failing to reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU)
- Record
GHSA-j75v-5pm7-3cg8- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-367
- Updated
- 2026-11-04
NVD
3.7
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
- Record
CVE-2026-67693- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-367
- Updated
- 2026-11-04
OSVBELL-CVE-2026-67693
3.7
CVE-2026-67693 does not affect BellSoft software
- Record
BELL-CVE-2026-67693- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-67693
3.7
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
- Record
DEBIAN-CVE-2026-67693- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-05
Show 4 moreShow less
OSVUBUNTU-CVE-2026-67693
3.7
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
- Record
UBUNTU-CVE-2026-67693- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-05
OSVAZL-107448 No score
CVE-2026-67693 affecting package gnutls 3.8.13-1
GnuTLS v3.8.13 does not reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU). NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
- Record
AZL-107448- Updated
- 2026-11-05
OSVROOT-OS-DEBIAN-12-CVE-2026-67693 No score
CVE-2026-67693 in gnutls28 - Patched by Root
Root has patched CVE-2026-67693 in the gnutls28 package for Root:Debian:12. Multiple fixed versions available.
- Record
ROOT-OS-DEBIAN-12-CVE-2026-67693- Updated
- 2026-11-02
OSVROOT-OS-DEBIAN-13-CVE-2026-67693 No score
CVE-2026-67693 in gnutls28 - Patched by Root
Root has patched CVE-2026-67693 in the gnutls28 package for Root:Debian:13. Multiple fixed versions available.
- Record
ROOT-OS-DEBIAN-13-CVE-2026-67693- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
gnutlsAzure Linux:3 |
through 3.8.13-1 | None known |
gnutls28Debian:12 |
All versions, plus listed versions 3.7.9-23.7.9-2+deb12u13.7.9-2+deb12u23.7.9-2+deb12u33.7.9-2+deb12u4 Show 40 moreShow less3.7.9-2+deb12u53.7.9-2+deb12u63.7.9-2+deb12u73.7.9-2+loong643.8.0+git20230413-13.8.0+git20230529-13.8.0+git20230713-13.8.1-13.8.1-23.8.1-33.8.1-43.8.10-13.8.10-23.8.10-33.8.11-13.8.11-23.8.11-33.8.12-13.8.12-23.8.12-33.8.12-43.8.13-13.8.2-13.8.3-13.8.3-1.13.8.3-1.1~exp13.8.4-13.8.4-23.8.5-13.8.5-23.8.5-33.8.5-43.8.6-13.8.6-23.8.7.1-13.8.8-13.8.8-23.8.9-13.8.9-23.8.9-3 |
None known |
gnutls28Debian:13 |
All versions, plus listed versions 3.8.10-13.8.10-23.8.10-33.8.11-13.8.11-2 Show 11 moreShow less3.8.11-33.8.12-13.8.12-23.8.12-33.8.12-43.8.13-13.8.9-33.8.9-3+deb13u13.8.9-3+deb13u23.8.9-3+deb13u33.8.9-3+deb13u4 |
None known |
gnutls28Debian:14 |
All versions, plus listed versions 3.8.10-13.8.10-23.8.10-33.8.11-13.8.11-2 Show 7 moreShow less3.8.11-33.8.12-13.8.12-23.8.12-33.8.12-43.8.13-13.8.9-3 |
None known |
gnutls28Root:Debian:12 |
before 3.7.9-2+deb12u7.aikido.5 | 3.7.9-2+deb12u7.aikido.5 |
rootio-gnutls28Root:Debian:12 |
before 3.7.9-2+deb12u7.aikido.5 | 3.7.9-2+deb12u7.aikido.5 |
gnutls28Root:Debian:13 |
before 3.8.9-3+deb13u4.aikido.3 | 3.8.9-3+deb13u4.aikido.3 |
rootio-gnutls28Root:Debian:13 |
before 3.8.9-3+deb13u4.aikido.3 | 3.8.9-3+deb13u4.aikido.3 |
gnutls26Ubuntu:Pro:14.04:LTS |
All versions, plus listed versions 2.12.23-1ubuntu42.12.23-1ubuntu52.12.23-12ubuntu12.12.23-12ubuntu22.12.23-12ubuntu2.1 Show 8 moreShow less2.12.23-12ubuntu2.22.12.23-12ubuntu2.32.12.23-12ubuntu2.42.12.23-12ubuntu2.52.12.23-12ubuntu2.62.12.23-12ubuntu2.72.12.23-12ubuntu2.82.12.23-12ubuntu2.10+esm1 |
None known |
gnutls28Ubuntu:Pro:16.04:LTS |
All versions, plus listed versions 3.3.15-5ubuntu23.3.18-1ubuntu13.3.20-1ubuntu13.4.9-2ubuntu13.4.10-4ubuntu1 Show 13 moreShow less3.4.10-4ubuntu1.13.4.10-4ubuntu1.23.4.10-4ubuntu1.33.4.10-4ubuntu1.43.4.10-4ubuntu1.53.4.10-4ubuntu1.63.4.10-4ubuntu1.73.4.10-4ubuntu1.83.4.10-4ubuntu1.93.4.10-4ubuntu1.9+esm13.4.10-4ubuntu1.9+esm23.4.10-4ubuntu1.9+esm33.4.10-4ubuntu1.9+esm4 |
None known |
Show 9 moreShow less
| Package | Affected | Fixed |
|---|---|---|
gnutls28Ubuntu:Pro:18.04:LTS |
All versions, plus listed versions 3.5.8-6ubuntu33.5.17-1ubuntu13.5.17-1ubuntu33.5.18-1ubuntu13.5.18-1ubuntu1.1 Show 9 moreShow less3.5.18-1ubuntu1.23.5.18-1ubuntu1.33.5.18-1ubuntu1.43.5.18-1ubuntu1.53.5.18-1ubuntu1.63.5.18-1ubuntu1.6+esm13.5.18-1ubuntu1.6+esm23.5.18-1ubuntu1.6+esm33.5.18-1ubuntu1.6+esm4 |
None known |
gnutls28Ubuntu:Pro:20.04:LTS |
All versions, plus listed versions 3.6.9-5ubuntu13.6.9-5ubuntu23.6.10-53.6.11.1-23.6.11.1-2ubuntu2 Show 14 moreShow less3.6.13-2ubuntu13.6.13-2ubuntu1.13.6.13-2ubuntu1.23.6.13-2ubuntu1.33.6.13-2ubuntu1.63.6.13-2ubuntu1.73.6.13-2ubuntu1.83.6.13-2ubuntu1.93.6.13-2ubuntu1.103.6.13-2ubuntu1.113.6.13-2ubuntu1.123.6.13-2ubuntu1.12+esm13.6.13-2ubuntu1.12+esm23.6.13-2ubuntu1.12+esm3 |
None known |
gnutls28Ubuntu:22.04:LTS |
All versions, plus listed versions 3.7.1-5ubuntu13.7.2-2ubuntu13.7.2-4ubuntu13.7.2-5ubuntu13.7.3-4ubuntu1 Show 9 moreShow less3.7.3-4ubuntu1.13.7.3-4ubuntu1.23.7.3-4ubuntu1.33.7.3-4ubuntu1.43.7.3-4ubuntu1.53.7.3-4ubuntu1.63.7.3-4ubuntu1.73.7.3-4ubuntu1.83.7.3-4ubuntu1.9 |
None known |
gnutls28Ubuntu:Pro:FIPS-preview:22.04:LTS |
All versions, plus listed versions 3.7.3-4ubuntu1.2+Fips1.1 |
None known |
gnutls28Ubuntu:Pro:FIPS-updates:22.04:LTS |
All versions, plus listed versions 3.7.3-4ubuntu1.2+Fips1.13.7.3-4ubuntu1.3+Fips1.13.7.3-4ubuntu1.4+Fips13.7.3-4ubuntu1.5+Fips13.7.3-4ubuntu1.6+Fips1 Show 4 moreShow less3.7.3-4ubuntu1.7+Fips13.7.3-4ubuntu1.7+Fips1.13.7.3-4ubuntu1.8+Fips1.13.7.3-4ubuntu1.9+Fips1 |
None known |
gnutls28Ubuntu:24.04:LTS |
All versions, plus listed versions 3.8.1-4ubuntu13.8.1-4ubuntu63.8.1-4ubuntu73.8.3-1ubuntu13.8.3-1.1ubuntu2 Show 7 moreShow less3.8.3-1.1ubuntu33.8.3-1.1ubuntu3.13.8.3-1.1ubuntu3.23.8.3-1.1ubuntu3.33.8.3-1.1ubuntu3.43.8.3-1.1ubuntu3.53.8.3-1.1ubuntu3.6 |
None known |
gnutls28Ubuntu:Pro:FIPS-updates:24.04:LTS |
All versions, plus listed versions 3.8.3-1.1ubuntu3.1+Fips13.8.3-1.1ubuntu3.4+Fips13.8.3-1.1ubuntu3.4+Fips1.13.8.3-1.1ubuntu3.5+Fips1.13.8.3-1.1ubuntu3.6+Fips1.2 |
None known |
gnutls28Ubuntu:26.10 |
All versions, plus listed versions 3.8.12-2ubuntu13.8.12-2ubuntu1.13.8.13-1ubuntu1 |
None known |
gnutls28Ubuntu:26.04:LTS |
All versions, plus listed versions 3.8.9-3ubuntu23.8.10-3ubuntu13.8.12-2ubuntu13.8.12-2ubuntu1.1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| references | EUVD | |
| description, references | CVE List | |
| description, facts, references, status | CVE List | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-67693 is a low vulnerability (CVSS 3.7) in gnutls, published October 8, 2026. Its validity is disputed. EPSS puts the chance of exploitation in the next 30 days at 0.17%, the 5th percentile. Fixed in gnutls28 3.7.9-2+deb12u7.aikido.5.
References
gitlab.com/gnutls/gnutls/-/blob/3.8.13/lib/x509/verify.c
gist.github.com/lkloliver/6fbfc191bc6163942c8017551ac3f238
gitlab.com/gnutls/gnutls/-/work_items/1642
gitlab.com/gnutls/gnutls/-/work_items/1965
gitlab.com/gnutls/gnutls/-/blob/e2169a87c7fb91935c2845088204b102baed4c5f/SECURITY.md
github.com/lkloliver/poc/tree/main/CVE-2026-67693