SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-30640

A vulnerability in the JNDI Realm of Apache Tomcat allows an attacker to authenticate using variations of a valid user name and/or to bypass some of the protection provided by the LockOut Realm.

MEDIUM 6.5EPSS 9.89%

Does this matter?

Lower severity and a low EPSS score (9.89%). Track it; it rarely justifies an emergency change on its own.

Description

A vulnerability in the JNDI Realm of Apache Tomcat allows an attacker to authenticate using variations of a valid user name and/or to bypass some of the protection provided by the LockOut Realm. This issue affects Apache Tomcat 10.0.0-M1 to 10.0.5; 9.0.0.M1 to 9.0.45; 8.5.0 to 8.5.65.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N
EPSS
9.89% probability · 96th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-116
Affected
apache/tomcat · oracle/communications cloud native core policy · oracle/communications diameter signaling router · oracle/communications pricing design center · oracle/hospitality cruise shipboard property management system · oracle/tekelec platform distribution · debian/debian linux
Source
security@apache.org
EPSS trend
0%5%10%26 October 2026: 9.89%26 October 202626 October 2026

EPSS 9.9% since 26 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.