CVE-2025-59089
Vulnérabilité moyenne dans kdcproxy (latchset)
Description
If an attacker causes kdcproxy to connect to an attacker-controlled KDC server (e.g. through server-side request forgery), they can exploit the fact that kdcproxy does not enforce bounds on TCP response length to conduct a denial-of-service attack. While receiving the KDC's response, kdcproxy copies the entire buffered stream into a new buffer on each recv() call, even when the transfer is incomplete, causing excessive memory allocation and CPU usage. Additionally, kdcproxy accepts incoming response chunks as long as the received data length is not exactly equal to the length indicated in the response header, even when individual chunks or the total buffer exceed the maximum length of a Kerberos message. This allows an attacker to send unbounded data until the connection timeout is reached (approximately 12 seconds), exhausting server memory or CPU resources. Multiple concurrent requests can cause accept queue overflow, denying service to legitimate clients.
Gravité et risque d'exploitation
CVE-2025-59089 obtient un score CVSS de 5.9/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.56 %, ce qui la place devant 45.5 % des CVE référencées.
Que faire ?
- Vérifiez si kdcproxy (versions 8100020251028161822.823393f5, 0:1.0.0-7.el9_0.1, 0:1.0.0-19.el10_0, 0:0.3.2-3.el7_9.3, 8040020251103205102.5b01ab7e, 8100020251103113748.143e9e98, 0:1.0.0-9.el9_7, 0:1.0.0-7.el9_2.1, 0:1.0.0-7.el9_4.1, 8060020251030180424.ada582f1, <1.1.0, 0, 0:1.0.0-19.el10_1, 0:1.0.0-9.el9_6, 8080020251029082621.b0a6ceea, <*, 8020020251106022345.792f4060) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://access.redhat.com/errata/RHSA-2025:21138
- https://access.redhat.com/errata/RHSA-2025:21139
- https://access.redhat.com/errata/RHSA-2025:21140
- https://access.redhat.com/errata/RHSA-2025:21141
- https://access.redhat.com/errata/RHSA-2025:21142
- https://access.redhat.com/errata/RHSA-2025:21448
- https://access.redhat.com/errata/RHSA-2025:21748
- https://access.redhat.com/errata/RHSA-2025:21806
- https://access.redhat.com/errata/RHSA-2025:21818
- https://access.redhat.com/errata/RHSA-2025:21819
- https://access.redhat.com/errata/RHSA-2025:21820
- https://access.redhat.com/errata/RHSA-2025:21821
- https://access.redhat.com/errata/RHSA-2025:22982
- https://access.redhat.com/security/cve/CVE-2025-59089
- https://bugzilla.redhat.com/show_bug.cgi?id=2393958
- https://github.com/latchset/kdcproxy/commit/c7675365aa20be11f03247966336c7613cac84e1
- https://github.com/latchset/kdcproxy/pull/68
