Description
A vulnerability in the MIT Kerberos implementation allows GSSAPI-protected messages using RC4-HMAC-MD5 to be spoofed due to weaknesses in the MD5 checksum design. If RC4 is preferred over stronger encryption types, an attacker could exploit MD5 collisions to forge message integrity codes. This may lead to unauthorized message tampering.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | krb5 | < 1.22 | 1.22 |
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 8.2 Advanced Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Telecommunications Update Service | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Extended Update Support | — | — |
| Red Hat | Red Hat Discovery 2 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | krb5 | 1.21.2-1 | — |
| Debian 13 | krb5 | 1.21.2-1 | — |
| Debian 12 | krb5 | 1.20.1-2+deb12u4 | — |
| Debian 11 | krb5 | 1.18.3-6+deb11u7 | DLA-4195-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | krb5 | 1.20.1-6ubuntu2.6 | USN-7542-1 |
| Ubuntu 22.04 LTS | krb5 | 1.19.2-2ubuntu0.7 | USN-7542-1 |
| Ubuntu 20.04 LTS | krb5 | 1.17-6ubuntu4.11 | USN-7542-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | krb5 | 1.16-2ubuntu0.4+esm5 | USN-7542-1 |
| Ubuntu Pro 16.04 LTS | krb5 | 1.13.2+dfsg-5ubuntu2.2+esm7 | USN-7542-1 |
| Ubuntu Pro 14.04 LTS | krb5 | 1.12+dfsg-2ubuntu5.4+esm7 | USN-7542-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | krb5 +7 | 1.21.3-8.el10_0 | RHSA-2025:9418 |
| RHEL 9 | krb5 +7 | 1.21.1-8.el9_6 | RHSA-2025:9430 |
| RHEL 8 | krb5 +7 | 1.18.2-32.el8_10 | RHSA-2025:8411 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.4 EUS | krb5 +7 | 1.21.1-2.el9_4.2 | RHSA-2025:13664 |
| RHEL 9.2 E4S | krb5 +7 | 1.20.1-9.el9_2.3 | RHSA-2025:13777 |
| RHEL 9.0 E4S | krb5 +7 | 1.19.1-16.el9_0.4 | RHSA-2025:15000 |
| RHEL 8.8 TUS | krb5 +7 | 1.18.2-26.el8_8.5 | RHSA-2025:15004 |
| RHEL 8.8 E4S | krb5 +7 | 1.18.2-26.el8_8.5 | RHSA-2025:15004 |
| RHEL 8.6 TUS | krb5 +7 | 1.18.2-16.el8_6.4 | RHSA-2025:15001 |
| RHEL 8.6 E4S | krb5 +7 | 1.18.2-16.el8_6.4 | RHSA-2025:15001 |
| RHEL 8.6 AUS | krb5 +7 | 1.18.2-16.el8_6.4 | RHSA-2025:15001 |
| RHEL 8.4 EUS Long Life | krb5 +7 | 1.18.2-9.el8_4.3 | RHSA-2025:15003 |
| RHEL 8.4 AUS | krb5 +7 | 1.18.2-9.el8_4.3 | RHSA-2025:15003 |
| RHEL 8.2 AUS | krb5 +7 | 1.17-19.el8_2.3 | RHSA-2025:15002 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | libkadm5 +6 | 1.21.3-8.el10_0 | ALSA-2025:9418 |
| AlmaLinux 9 | libkadm5 +6 | 1.21.1-8.el9_6 | ALSA-2025:9430 |
| AlmaLinux 8 | libkadm5 +6 | 1.18.2-32.el8_10 | ALSA-2025:8411 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | krb5 | 1.21.3-8.el10_0 | RLSA-2025:9418 |
| Rocky Linux 9 | krb5 | 1.21.1-8.el9_6 | RLSA-2025:9430 |
| Rocky Linux 8 | krb5 | 1.18.2-32.el8_10 | RLSA-2025:8411 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | krb5 | 1.20.1-150600.11.14.1 | SUSE-SU-2025:3699-1 |
| SLES 15 SP6 | krb5 | 1.20.1-150600.11.14.1 | SUSE-SU-2025:3699-1 |
| SLES 12 SP5 | krb5 | 1.16.3-46.21.1 | SUSE-SU-2025:3698-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.0 | krb5 | 1.20.1-7.1 | SUSE-SU-2025:20719-1 |
| SLE Micro 5.5 | krb5 | 1.20.1-150500.3.17.1 | SUSE-SU-2025:03270-1 |
| SLE Micro 5.4 | krb5 | 1.19.2-150400.3.18.1 | SUSE-SU-2025:3729-1 |
| SLE Micro 5.3 | krb5 | 1.19.2-150400.3.18.1 | SUSE-SU-2025:3729-1 |
| SLE Micro 5.2 | krb5 | 1.19.2-150300.25.1 | SUSE-SU-2025:03227-1 |
| SLE Micro 5.1 | krb5 | 1.19.2-150300.25.1 | SUSE-SU-2025:03227-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | krb5 | 1.20.1-150600.11.14.1 | SUSE-SU-2025:3699-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libkadm5 +6 | 1.21.3-6.amzn2023.0.1 | ALAS2023-2025-1173 |
| Amazon Linux 2 | libkadm5 +6 | 1.15.1-55.amzn2.2.9 | ALAS2-2025-2985 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | krb5 | 1.19.4-4 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | libkadm5 +6 | 1.21.3-8.0.1.el10_0 | ELSA-2025-9418 |
| Oracle Linux 9 | libkadm5 +6 | 1.21.1-8.0.1.el9_6 | ELSA-2025-9430 |
| Oracle Linux 8 | libkadm5 +6 | 1.18.2-32.0.1.el8_10 | ELSA-2025-8411 |
Advisories 37
- ALSA-2025:9418 Moderate: krb5 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2025:9430 Moderate: krb5 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2025:8411 Moderate: krb5 security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2025:9430 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:9418 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:8411 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:15004 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:15002 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:15003 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:15000 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:15001 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:13777 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- RHSA-2025:13664 Red Hat Security Advisory: krb5 security update Red Hat Security Advisories (RHSA) · Sep 2, 2026
- WID-SEC-2026-1730 Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Jul 16, 2026
- USN-7542-1 krb5 vulnerability Ubuntu Security Notices (USN) · Jun 25, 2026
- ICSA-26-134-16 Siemens Ruggedcom Rox CISA ICS & IT advisories · May 14, 2026
- NCSC-2026-0147 Kwetsbaarheden verholpen in Siemens-producten NCSC-NL (Netherlands) · May 13, 2026
- SSA-577017 SSA-577017: Multiple Vulnerabilities in Ruggedcom Rox Before 2.17.1 Siemens ProductCERT · May 12, 2026
- WID-SEC-2026-0778 Dell Secure Connect Gateway Policy Manager: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 11, 2026
- WID-SEC-2025-0795 MIT Kerberos: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen BSI CERT-Bund (WID) · Mar 23, 2026
- SUSE-SU-2025:3729-1 Security update for krb5 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20719-1 Security update for krb5 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:03227-1 Security update for krb5 SUSE / openSUSE Security Updates · Mar 23, 2026
- DLA-4195-1 krb5 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2025:3698-1 Security update for krb5 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:3699-1 Security update for krb5 SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2025-2361 Oracle Communications: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 17, 2025
- NCSC-2025-0330 Kwetsbaarheden verholpen in Oracle Communications producten NCSC-NL (Netherlands) · Oct 23, 2025
- RLSA-2025:9418 Moderate: krb5 security update Rocky Linux Security Advisories · Oct 8, 2025
- RLSA-2025:9430 Moderate: krb5 security update Rocky Linux Security Advisories · Oct 7, 2025
- SUSE-SU-2025:03270-1 Security update for krb5 SUSE / openSUSE Security Updates · Sep 18, 2025
- ALAS2023-2025-1173 Moderate: krb5 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Sep 8, 2025
- ALAS2-2025-2985 Moderate: krb5 security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Sep 4, 2025
- RLSA-2025:8411 Moderate: krb5 security update Rocky Linux Security Advisories · Jul 29, 2025
- ELSA-2025-9418 Moderate: krb5 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jun 27, 2025
- ELSA-2025-9430 Moderate: krb5 security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jun 24, 2025
- ELSA-2025-8411 Moderate: krb5 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jun 3, 2025
References
- RHSA-2025:11487 vendor-advisory
- RHSA-2025:13664 vendor-advisory
- RHSA-2025:13777 vendor-advisory
- RHSA-2025:15000 vendor-advisory
- RHSA-2025:15001 vendor-advisory
- RHSA-2025:15002 vendor-advisory
- RHSA-2025:15003 vendor-advisory
- RHSA-2025:15004 vendor-advisory
- RHSA-2025:8411 vendor-advisory
- RHSA-2025:9418 vendor-advisory
- RHSA-2025:9430 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2025-3576 vdb-entry
- RHBZ#2359465 issue-tracking
- https://web.mit.edu/kerberos/krb5-1.22/krb5-1.22.html