CyberSecBulletin
CVE-2026-57915NVD status: Deferred

Apache Kerby: Missing Critical Step in Authentication

CVE-2026-57915 is a high-severity missing critical step in authentication vulnerability in Apache Kerby from Apache, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 2.1.2 as the first without the flaw, so updating Apache Kerby to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.53% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache Kerby to 2.1.2 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache Kerbybefore 2.1.22.1.2
Red HatRed Hat AMQ ClientsNot specified in the recordNot stated
Red HatRed Hat Data Grid 8Not specified in the recordNot stated
Red HatRed Hat Fuse 7Not specified in the recordNot stated
Red HatRed Hat JBoss Enterprise Application Platform Expansion PackNot specified in the recordNot stated
Red Hatstreams for Apache Kafka 2Not specified in the recordNot stated
Red Hatstreams for Apache Kafka 3Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
LowSome restricted data can be read.
Integrity
LowLimited modification of data is possible.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L. Scored by CNA.

Scoring systemScoreSeverityScored by
CVSS 3.17.3HighCISA (ADP)
CVSS 3.17.3HighCNA

Official description

It is possible to bypass the Kerberos pre-authentication check in Apache Kerby by sending a PA-DATA with an unrecognized or unsupported type. Users are recommended to upgrade to version 2.1.2, which fixes this issue.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Missing Critical Step in Authentication

The product implements an authentication technique, but it skips a step that weakens the technique.

More Missing Critical Step in Authentication vulnerabilities (CWE-304)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Missing Critical Step in Authentication vulnerabilities

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