Allocation of Resources Without Limits or Throttling Affecting python-kdcproxy package, versions *


Severity

Recommended
low

Based on Debian security rating.

Threat Intelligence

EPSS
0.08% (24th percentile)

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  • Snyk IDSNYK-DEBIAN12-PYTHONKDCPROXY-13916497
  • published13 Nov 2025
  • disclosed12 Nov 2025

Introduced: 12 Nov 2025

NewCVE-2025-59089  (opens in a new tab)
CWE-770  (opens in a new tab)

How to fix?

There is no fixed version for Debian:12 python-kdcproxy.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-kdcproxy package and not the python-kdcproxy package as distributed by Debian. See How to fix? for Debian:12 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1