CVE-2026-55957Public exploitNetwork attack vector

Unauthenticated access via skipped GSSAPI password validation

Published Jun 29, 2026 · Updated Jun 29, 2026

Authentication bypass in Apache Tomcat allows remote attackers to access protected resources without supplying the correct password. JNDIRealm's bindAsUser method leaves GSSAPI SASL enabled when adding supplied credentials to the LDAP context, so the bind can reuse GSSAPI authentication instead of validating the password. Exposure requires JNDIRealm to authenticate binds with GSSAPI and a login path such as HttpServletRequest.login; successful exploitation grants the target account's protected access.

CVSS severity7.3
High
EPSS probability2.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Apache Tomcat allows remote attackers to access protected resources without supplying the correct password. JNDIRealm's bindAsUser method leaves GSSAPI SASL enabled when adding supplied credentials to the LDAP context, so the bind can reuse GSSAPI authentication instead of validating the password. Exposure requires JNDIRealm to authenticate binds with GSSAPI and a login path such as HttpServletRequest.login; successful exploitation grants the target account's protected access.

The record

CVE
CVE-2026-55957
Published
Jun 29, 2026
Updated
Jun 29, 2026
Vendor
The Apache Software Foundation
Product
Apache Tomcat
Classifications
CWE-304, T1078
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 29, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.1.0-M1 <=10.1.36
  2. Affected versionversion=11.0.0-M1 <=11.0.4
  3. Affected versionversion=7.0.0 <=7.0.109
  4. Affected versionversion=8.5.0 <=8.5.100
  5. Affected versionversion=9.0.0.M1 <=9.0.100

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Tomcatversion=10.1.0-M1 <=10.1.36; version=11.0.0-M1 <=11.0.4; version=7.0.0 <=7.0.109; version=8.5.0 <=8.5.100; version=9.0.0.M1 <=9.0.100

Published CVSS scores

7.3GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-304Missing Critical Step in Authentication
T1078Valid Accounts

Public exploit references

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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