CVE-2025-59089Network attack vector

Service interruption via unbounded TCP response buffering

Published Nov 12, 2025 · Updated Nov 12, 2025

Resource exhaustion in Red Hat Enterprise Linux's kdcproxy allows remote attackers to interrupt service via a malicious KDC response. Application.__handle_recv() repeatedly exports the growing stream and accepts data beyond both the Kerberos maximum and header length. Reachability requires steering kdcproxy to an attacker-controlled KDC; concurrent requests can exhaust CPU or memory and overflow the accept queue.

CVSS severity5.9
Medium
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Red Hat Enterprise Linux's kdcproxy allows remote attackers to interrupt service via a malicious KDC response. Application.__handle_recv() repeatedly exports the growing stream and accepts data beyond both the Kerberos maximum and header length. Reachability requires steering kdcproxy to an attacker-controlled KDC; concurrent requests can exhaust CPU or memory and overflow the accept queue.

The record

CVE
CVE-2025-59089
Published
Nov 12, 2025
Updated
Nov 12, 2025
Vendor
389 Directory Server
Product
Red Hat Enterprise Linux 10
Classifications
CWE-770, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 12, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 12, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 7Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 10.0 Extended Update SupportAffected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9.6 Extended Update SupportAffected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.

Published CVSS scores

5.9Red HatCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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