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) * krb5: MIT Kerberos 5: Denial of Service via NULL pointer dereference in NegoEx mechanism (CVE-2026-40355) 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.
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) * krb5: MIT Kerberos 5: Denial of Service via NULL pointer dereference in NegoEx mechanism (CVE-2026-40355) 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
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:16799
- Cve Count
- 2
- Additional Cves
- ["CVE-2026-40356"]
- State
- PUBLISHED
Threat ID: 6a175eeee29bf47b50edd24d
Added to database: 05/27/2026, 21:15:26 UTC
Last enriched: 07/19/2026, 23:07:15 UTC
Last updated: 09/13/2026, 22:01:33 UTC
Views: 114
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