Description
pam_krb5 2.2.14 in Red Hat Enterprise Linux (RHEL) 5 and earlier, when the existing_ticket option is enabled, uses incorrect privileges when reading a Kerberos credential cache, which allows local users to gain privileges by setting the KRB5CCNAME environment variable to an arbitrary cache filename and running the (1) su or (2) sudo program. NOTE: there may be a related vector involving sshd that has limited relevance.
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.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | pam_krb5 | 2.2.14-1.el5_2.1 | RHSA-2008:0907 |
Advisories 1
- RHSA-2008:0907 Red Hat Security Advisory: pam_krb5 security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
References
- https://bugzilla.redhat.com/show_bug.cgi?id=461960
- pamkrb5-existingticket-privilege-escalation(45635) vdb-entry
- RHSA-2008:0907 vendor-advisory
- 1020978 vdb-entry
- MDVSA-2008:209 vendor-advisory
- 32135 third-party-advisory
- SUSE-SR:2008:027 vendor-advisory
- 43314 third-party-advisory
- 32119 third-party-advisory
- 32174 third-party-advisory
- http://www.vmware.com/security/advisories/VMSA-2011-0003.html
- FEDORA-2008-8605 vendor-advisory
- FEDORA-2008-8618 vendor-advisory
- 20110211 VMSA-2011-0003 Third party component updates for VMware vCenter Server, vCenter Update Manager, ESXi and ESX mailing-list
- oval:org.mitre.oval:def:10923 vdb-entry signature
- 31534 vdb-entry