CVE-2025-59089

Summary

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.

Affected Software

VendorProductVersion RangeStatus
latchsetkdcproxy0 < 1.1.0affected
Red HatRed Hat Enterprise Linux 100:1.0.0-19.el10_1 < *unaffected
Red HatRed Hat Enterprise Linux 10.0 Extended Update Support0:1.0.0-19.el10_0 < *unaffected
Red HatRed Hat Enterprise Linux 7 Extended Lifecycle Support0:0.3.2-3.el7_9.3 < *unaffected
Red HatRed Hat Enterprise Linux 88100020251103113748.143e9e98 < *unaffected
Red HatRed Hat Enterprise Linux 88100020251028161822.823393f5 < *unaffected
Red HatRed Hat Enterprise Linux 8.2 Advanced Update Support8020020251106022345.792f4060 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support8040020251103205102.5b01ab7e < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On8040020251103205102.5b01ab7e < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support8060020251030180424.ada582f1 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Telecommunications Update Service8060020251030180424.ada582f1 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Update Services for SAP Solutions8060020251030180424.ada582f1 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Service8080020251029082621.b0a6ceea < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutions8080020251029082621.b0a6ceea < *unaffected
Red HatRed Hat Enterprise Linux 90:1.0.0-9.el9_7 < *unaffected
Red HatRed Hat Enterprise Linux 9.0 Update Services for SAP Solutions0:1.0.0-7.el9_0.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.2 Update Services for SAP Solutions0:1.0.0-7.el9_2.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.4 Extended Update Support0:1.0.0-7.el9_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.6 Extended Update Support0:1.0.0-9.el9_6 < *unaffected

Weaknesses

  • CWE-770: Allocation of Resources Without Limits or Throttling

Workarounds

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References