MUNGE is an authentication service for creating and validating user credentials. From 0.5 to 0.5.17, local attacker can exploit a buffer overflow vulnerability in munged (the MUNGE authentication daemon) to leak cryptographic key material from process memory. With the leaked key material, the attacker could forge arbitrary MUNGE credentials to impersonate any user (including root) to services that rely on MUNGE for authentication. The vulnerability allows a buffer overflow by sending a crafted message with an oversized address length field, corrupting munged's internal state and enabling extraction of the MAC subkey used for credential verification. This vulnerability is fixed in 0.5.18.
https://lists.debian.org/debian-lts-announce/2026/02/msg00015.html
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-25506.json
https://github.com/dun/munge/security/advisories/GHSA-r9cr-jf4v-75gh
https://github.com/dun/munge/releases/tag/munge-0.5.18
https://github.com/dun/munge/commit/bf40cc27c4ce8451d4b062c9de0b67ec40894812
https://bugzilla.redhat.com/show_bug.cgi?id=2438715
https://access.redhat.com/security/cve/CVE-2026-25506
https://access.redhat.com/errata/RHSA-2026:3034
https://access.redhat.com/errata/RHSA-2026:3033
https://access.redhat.com/errata/RHSA-2026:3032
https://access.redhat.com/errata/RHSA-2026:3013
https://access.redhat.com/errata/RHSA-2026:3012
https://access.redhat.com/errata/RHSA-2026:3011
https://access.redhat.com/errata/RHSA-2026:3010
https://access.redhat.com/errata/RHSA-2026:2954
https://access.redhat.com/errata/RHSA-2026:2949
https://access.redhat.com/errata/RHSA-2026:2934
https://access.redhat.com/errata/RHSA-2026:2923