Red Hat Security Advisory: krb5 security update
Kerberos is a network authentication system, which can improve the security of your network by eliminating the insecure practice of sending passwords over the network in unencrypted form. It allows clients and servers to authenticate to each other with the help of a trusted third party, the Kerberos key distribution center (KDC). Security Fix(es): * krb5: MIT Kerberos 5 (krb5): Denial of Service via integer underflow and out-of-bounds read (CVE-2026-40356) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
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
Kerberos is a network authentication system, which can improve the security of your network by eliminating the insecure practice of sending passwords over the network in unencrypted form. It allows clients and servers to authenticate to each other with the help of a trusted third party, the Kerberos key distribution center (KDC). Security Fix(es): * krb5: MIT Kerberos 5 (krb5): Denial of Service via integer underflow and out-of-bounds read (CVE-2026-40356) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
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
- State
- PUBLISHED
Threat ID: 6a27e9808dd33fbd85167aa3
Added to database: 06/09/2026, 10:22:56 UTC
Last enriched: 07/23/2026, 01:01:12 UTC
Last updated: 09/14/2026, 10:01:30 UTC
Views: 175
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