High severity · published Jun 29, 2026
CVE-2026-55957
Apache Tomcat: Authentication bypass with JNDIRealm and GSSAPI authenticated bind
7.3
CVSS
2.9%
EPSS
No
On KEV
Description
Missing Critical Step in Authentication vulnerability in Apache Tomcat when the JNDIRealm was configured to authenticate binds using GSSAPI allowed attackers to authenticate without provided the correct password.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.4, from 10.1.0-M1 through 10.1.36, from 9.0.0.M1 through 9.0.100, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109.
Users are recommended to upgrade to version 11.0.5, 10.1.37 or 9.0.101, which fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.9% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tomcat · Apache
11.0.0-M1 through 11.0.4; 10.1.0-M1 through 10.1.36; 9.0.0.M1 through 9.0.100; 8.5.0 through 8.5.100; 7.0.0 through 7.0.109 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55957
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55957
Vendor Advisory
https://lists.apache.org/thread/7fk339o5jvd4mcgsf0chbrn4o525ccjh
Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/06/29/26
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