Red Hat Security Advisory: krb5 security update
A denial of service vulnerability (CVE-2026-40356) exists in MIT Kerberos 5 (krb5) due to an integer underflow and out-of-bounds read. This vulnerability affects Red Hat Enterprise Linux 9.4 and related distributions. The issue could cause the krb5 service to crash or behave unexpectedly. Red Hat has issued an important security advisory with updates to address this vulnerability.
AI Analysis
Technical Summary
The vulnerability CVE-2026-40356 in MIT Kerberos 5 (krb5) involves an integer underflow and out-of-bounds read that can lead to denial of service. Kerberos is a network authentication system that uses a trusted third party (KDC) to authenticate clients and servers. The issue affects Red Hat Enterprise Linux 9.6 Extended Update Support versions across multiple architectures including x86_64, aarch64, ppc64le, and s390x. Red Hat Product Security has rated this update as Important and released patches to fix the vulnerability. No CVSS score is provided in the advisory.
Potential Impact
Successful exploitation of this vulnerability can cause a denial of service condition in the krb5 service, potentially disrupting authentication services that rely on Kerberos. There is no indication of code execution or privilege escalation. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated krb5 packages for Red Hat Enterprise Linux 9.6 Extended Update Support to address this vulnerability. Users should apply the official Red Hat security update as described in the advisory RHSA-2026:24683. For detailed update instructions, refer to https://access.redhat.com/articles/11258. Patch status is confirmed with an official fix available.
Red Hat Security Advisory: krb5 security update
Description
A denial of service vulnerability (CVE-2026-40356) exists in MIT Kerberos 5 (krb5) due to an integer underflow and out-of-bounds read. This vulnerability affects Red Hat Enterprise Linux 9.4 and related distributions. The issue could cause the krb5 service to crash or behave unexpectedly. Red Hat has issued an important security advisory with updates to address this vulnerability.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-40356 in MIT Kerberos 5 (krb5) involves an integer underflow and out-of-bounds read that can lead to denial of service. Kerberos is a network authentication system that uses a trusted third party (KDC) to authenticate clients and servers. The issue affects Red Hat Enterprise Linux 9.6 Extended Update Support versions across multiple architectures including x86_64, aarch64, ppc64le, and s390x. Red Hat Product Security has rated this update as Important and released patches to fix the vulnerability. No CVSS score is provided in the advisory.
Potential Impact
Successful exploitation of this vulnerability can cause a denial of service condition in the krb5 service, potentially disrupting authentication services that rely on Kerberos. There is no indication of code execution or privilege escalation. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated krb5 packages for Red Hat Enterprise Linux 9.6 Extended Update Support to address this vulnerability. Users should apply the official Red Hat security update as described in the advisory RHSA-2026:24683. For detailed update instructions, refer to https://access.redhat.com/articles/11258. Patch status is confirmed with an official fix available.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:24686
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a27e9808dd33fbd85167aa3
Added to database: 06/09/2026, 10:22:56 UTC
Last enriched: 07/23/2026, 01:01:12 UTC
Last updated: 07/31/2026, 19:24:47 UTC
Views: 146
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