CVE-2025-59089: latchset kdcproxy · Unthrottled Resource Allocation
Affects latchset kdcproxySource CVE Database V5
Not known to be exploited · CVSS 5.9 Medium.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 12 Nov 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHublatchset/kdcproxypkg:github/latchset/kdcproxyOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
An official fix is available from Red Hat. Users should apply the python-kdcproxy security update provided in Red Hat Enterprise Linux 9.6, 9.8, and Extended Update Support and Extended Life Cycle releases. Refer to Red Hat advisory RHSA-2025:21138 and RHSA-2025:21139 and the update instructions at https://access.redhat.com/articles/11258. No additional mitigation is required once the patch is applied.
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.
References
- access.redhat.com/errata/RHSA-2025:21138 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21139 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21140 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21141 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21142 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21448 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21748 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21806 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21818 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21819 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21820 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:21821 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:22982 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2025-59089 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2393958 (opens in a new tab)
- github.com/latchset/kdcproxy/commit/c7675365aa20be11f03247966336c7613cac84e1 (opens in a new tab)
- github.com/latchset/kdcproxy/pull/68 (opens in a new tab)