CVE-2021-25122

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

18.11% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 96.9% of scored records. A rank, not a probability.

NVD base score

7.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-10-08.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-03-01 12:00Z5 YR AGO

Last updated

2026-10-08 21:13Z20 DAYS AGO

Reserved

2021-01-14

Assigning CNA

apache

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-200Exposure of Sensitive Information to an Unauthorized ActorClass

Data version

5.2

Document digest

9d499ea2bfa7a73bb10b5875425fdabf1680c9e96d829984adf0bfda47a7d06c

• lists.apache.orghttps://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cannounce.tomcat.apache.org%3Ex_refsource_MISC
• lists.apache.org[tomcat-users] 20210301 [SECURITY] CVE-2021-25122 Apache Tomcat h2c request mix-uphttps://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cusers.tomcat.apache.org%3Emailing-listx_refsource_MLIST
• lists.apache.org[tomcat-dev] 20210301 [SECURITY] CVE-2021-25122 Apache Tomcat h2c request mix-uphttps://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cdev.tomcat.apache.org%3Emailing-listx_refsource_MLIST
• lists.apache.org[tomcat-dev] 20210301 svn commit: r1887027 - in /tomcat/site/trunk: docs/security-10.html docs/security-7.html docs/security-8.html docs/security-9.html xdocs/security-10.xml xdocs/security-7.xml xdocs/security-8.xml xdocs/security-9.xmlhttps://lists.apache.org/thread.html/rf6d5d57b114678d8898005faef31e9fd6d7c981fcc4ccfc3bc272fc9%40%3Cdev.tomcat.apache.org%3Emailing-listx_refsource_MLIST
• lists.apache.org[announce] 20210301 [SECURITY] CVE-2021-25122 Apache Tomcat h2c request mix-uphttps://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cannounce.apache.org%3Emailing-listx_refsource_MLIST
• www.openwall.com[oss-security] 20210301 CVE-2021-25122: Apache Tomcat h2c request mix-uphttp://www.openwall.com/lists/oss-security/2021/03/01/1mailing-listx_refsource_MLIST
• lists.apache.org[tomcat-users] 20210305 RE: [SECURITY] CVE-2021-25122 Apache Tomcat h2c request mix-uphttps://lists.apache.org/thread.html/rcd90bf36b1877e1310b87ecd14ed7bbb15da52b297efd9f0e7253a3b%40%3Cusers.tomcat.apache.org%3Emailing-listx_refsource_MLIST
• lists.apache.org[tomcat-users] 20210305 Re: [SECURITY] CVE-2021-25122 Apache Tomcat h2c request mix-uphttps://lists.apache.org/thread.html/rd0463f9a5cbc02a485404c4b990f0da452e5ac5c237808edba11c947%40%3Cusers.tomcat.apache.org%3Emailing-listx_refsource_MLIST
• lists.debian.org[debian-lts-announce] 20210316 [SECURITY] [DLA 2596-1] tomcat8 security updatehttps://lists.debian.org/debian-lts-announce/2021/03/msg00018.htmlmailing-listx_refsource_MLIST
• www.debian.orgDSA-4891https://www.debian.org/security/2021/dsa-4891vendor-advisoryx_refsource_DEBIAN
• www.oracle.comhttps://www.oracle.com//security-alerts/cpujul2021.htmlx_refsource_MISC
• security.netapp.comhttps://security.netapp.com/advisory/ntap-20210409-0002/x_refsource_CONFIRM
• www.oracle.comhttps://www.oracle.com/security-alerts/cpuoct2021.htmlx_refsource_MISC
• www.oracle.comhttps://www.oracle.com/security-alerts/cpujan2022.htmlx_refsource_MISC
• security.gentoo.orgGLSA-202208-34https://security.gentoo.org/glsa/202208-34vendor-advisoryx_refsource_GENTOO