CVE-2021-25122: Apache Tomcat h2c request mix-up

Published Mar 1, 2021
·
Updated

A flaw was found in Apache Tomcat. When responding to new h2c connection requests, Apache Tomcat could duplicate request headers and a limited amount of request body from one request to another meaning user A and user B could both see the results of user A's request. The highest threat from this vulnerability is to data confidentiality.

Other sources

Apache Tomcat could allow a remote attacker to obtain sensitive information, caused by a flaw when responding to new h2c connection requests. By sending a specially-crafted request, an attacker could exploit this vulnerability to see the request body information from one request to another, and use this information to launch further attacks against the affected system.

— IBM

When responding to new h2c connection requests, Apache Tomcat could duplicate request headers and a limited amount of request body from one request to another meaning user A and user B could both see the results of user A's request.

Upstream commits: Tomcat 10.0: https://github.com/apache/tomcat/commit/dd757c0a893e2e35f8bc1385d6967221ae8b9b9b Tomcat 9.0: https://github.com/apache/tomcat/commit/d47c20a776e8919eaca8da9390a32bc8bf8210b1 Tomcat 8.5: https://github.com/apache/tomcat/commit/bb0e7c1e0d737a0de7d794572517bce0e91d30fa

Reference: http://mail-archives.apache.org/modmbox/tomcat-announce/202103.mbox/%3Cb7626398-5e6d-1639-4e9e-e41b34af84de%40apache.org%3E

— Red Hat

When responding to new h2c connection requests, Apache Tomcat versions 10.0.0-M1 to 10.0.0, 9.0.0.M1 to 9.0.41 and 8.5.0 to 8.5.61 could duplicate request headers and a limited amount of request body from one request to another meaning user A and user B could both see the results of user A's request.

Affected Software

71 affected componentsFixes available
redhat/jws5-ecj<0:4.12.0-3.redhat_2.2.el7
0:4.12.0-3.redhat_2.2.el7
redhat/jws5-tomcat<0:9.0.43-11.redhat_00011.1.el7
0:9.0.43-11.redhat_00011.1.el7
redhat/jws5-tomcat-native<0:1.2.26-3.redhat_3.el7
0:1.2.26-3.redhat_3.el7
redhat/jws5-tomcat-vault<0:1.1.8-2.Final_redhat_00003.1.el7
0:1.1.8-2.Final_redhat_00003.1.el7
redhat/jws5-ecj<0:4.12.0-3.redhat_2.2.el8
0:4.12.0-3.redhat_2.2.el8
redhat/jws5-tomcat<0:9.0.43-11.redhat_00011.1.el8
0:9.0.43-11.redhat_00011.1.el8
redhat/jws5-tomcat-native<0:1.2.26-3.redhat_3.el8
0:1.2.26-3.redhat_3.el8
redhat/jws5-tomcat-vault<0:1.1.8-2.Final_redhat_00003.1.el8
0:1.1.8-2.Final_redhat_00003.1.el8
IBM IBM® Engineering Requirements Management DOORS<=9.7.2.7
IBM IBM® Engineering Requirements Management DOORS Web Access<=9.7.2.7
Apache Tomcat>=8.5.0<=8.5.61
Apache Tomcat>=9.0.0<=9.0.41
Apache Tomcat=9.0.0-milestone1
Apache Tomcat=9.0.0-milestone10
Apache Tomcat=9.0.0-milestone11
Apache Tomcat=9.0.0-milestone12
Apache Tomcat=9.0.0-milestone13
Apache Tomcat=9.0.0-milestone14
Apache Tomcat=9.0.0-milestone15
Apache Tomcat=9.0.0-milestone16
Apache Tomcat=9.0.0-milestone17
Apache Tomcat=9.0.0-milestone18
Apache Tomcat=9.0.0-milestone19
Apache Tomcat=9.0.0-milestone2
Apache Tomcat=9.0.0-milestone20
Apache Tomcat=9.0.0-milestone21
Apache Tomcat=9.0.0-milestone22
Apache Tomcat=9.0.0-milestone23
Apache Tomcat=9.0.0-milestone24
Apache Tomcat=9.0.0-milestone25
Apache Tomcat=9.0.0-milestone26
Apache Tomcat=9.0.0-milestone27
Apache Tomcat=9.0.0-milestone3
Apache Tomcat=9.0.0-milestone4
Apache Tomcat=9.0.0-milestone5
Apache Tomcat=10.0.0
Apache Tomcat=10.0.0-milestone1
Apache Tomcat=10.0.0-milestone10
Apache Tomcat=10.0.0-milestone2
Apache Tomcat=10.0.0-milestone3
Apache Tomcat=10.0.0-milestone4
Apache Tomcat=10.0.0-milestone5
Apache Tomcat=10.0.0-milestone6
Apache Tomcat=10.0.0-milestone7
Apache Tomcat=10.0.0-milestone8
Apache Tomcat=10.0.0-milestone9
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Oracle Agile PLM=9.3.3
Oracle Agile PLM=9.3.6
Oracle Communications Cloud Native Core Policy=1.14.0
Oracle Communications Cloud Native Core Security Edge Protection Proxy=1.6.0
Oracle Communications Instant Messaging Server=10.0.1.5.0
Oracle Database=12.2.0.1
Oracle Database=19c
Oracle Database=21c
Oracle Graph Server And Client<21.3.0
Oracle Graph Server And Client=21.3.0
Oracle Instantis Enterprisetrack=17.1
Oracle Instantis Enterprisetrack=17.2
Oracle Instantis Enterprisetrack=17.3
Oracle Managed File Transfer=12.2.1.3.0
Oracle Managed File Transfer=12.2.1.4.0
Oracle MySQL Enterprise Monitor<=8.0.23
Oracle Siebel UI Framework<=21.9
debian/tomcat9
9.0.43-2~deb11u109.0.43-2~deb11u129.0.70-29.0.95-1
redhat/tomcat<10.0.2
10.0.2
redhat/tomcat<9.0.43
9.0.43
redhat/tomcat<8.5.63
8.5.63
Oracle Agile Product Lifecycle Management=9.3.3
Oracle Agile Product Lifecycle Management=9.3.6

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/jws5-ecj to a version that resolves this vulnerability.

    Fixed in 0:4.12.0-3.redhat_2.2.el7
  2. Upgrade

    Upgrade redhat/jws5-tomcat to a version that resolves this vulnerability.

    Fixed in 0:9.0.43-11.redhat_00011.1.el7
  3. Upgrade

    Upgrade redhat/jws5-tomcat-native to a version that resolves this vulnerability.

    Fixed in 0:1.2.26-3.redhat_3.el7
  4. Upgrade

    Upgrade redhat/jws5-tomcat-vault to a version that resolves this vulnerability.

    Fixed in 0:1.1.8-2.Final_redhat_00003.1.el7
  5. Upgrade

    Upgrade redhat/jws5-ecj to a version that resolves this vulnerability.

    Fixed in 0:4.12.0-3.redhat_2.2.el8
  6. Upgrade

    Upgrade redhat/jws5-tomcat to a version that resolves this vulnerability.

    Fixed in 0:9.0.43-11.redhat_00011.1.el8
  7. Upgrade

    Upgrade redhat/jws5-tomcat-native to a version that resolves this vulnerability.

    Fixed in 0:1.2.26-3.redhat_3.el8
  8. Upgrade

    Upgrade redhat/jws5-tomcat-vault to a version that resolves this vulnerability.

    Fixed in 0:1.1.8-2.Final_redhat_00003.1.el8
  9. Upgrade

    Upgrade debian/tomcat9 to a version that resolves this vulnerability.

    Fixed in 9.0.43-2~deb11u10Fixed in 9.0.43-2~deb11u12Fixed in 9.0.70-2Fixed in 9.0.95-1
  10. Upgrade

    Upgrade redhat/tomcat to a version that resolves this vulnerability.

    Fixed in 10.0.2
  11. Upgrade

    Upgrade redhat/tomcat to a version that resolves this vulnerability.

    Fixed in 9.0.43
  12. Upgrade

    Upgrade redhat/tomcat to a version that resolves this vulnerability.

    Fixed in 8.5.63
  13. Upgrade

    Upgrade Apache Tomcat 10.0 to a version that resolves this vulnerability.

    Patch dd757c0a893e2e35f8bc1385d6967221ae8b9b9b
  14. Upgrade

    Upgrade Apache Tomcat 8.5 to a version that resolves this vulnerability.

    Patch bb0e7c1e0d737a0de7d794572517bce0e91d30fa
  15. Upgrade

    Upgrade Apache Tomcat 9.0 to a version that resolves this vulnerability.

    Patch d47c20a776e8919eaca8da9390a32bc8bf8210b1
  16. Compensating control

    If you cannot immediately patch, mitigate the h2c request mix-up by preventing use of h2c (HTTP/2 cleartext) on affected Apache Tomcat instances until the fix is applied.

Event History

Mar 1, 2021
CVE Published
12:00 AM
CVE Published
via MITRE·12:00 PM
Data Sourced
via MITRE·12:00 PM
DescriptionWeakness
Data Sourced
via NVD·12:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Mar 2, 2021
Data Sourced
via Red Hat·10:25 AM
DescriptionSeverityAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:54 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:31 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-25122?

The severity of CVE-2021-25122 is high.

2

Which versions of Apache Tomcat are affected by CVE-2021-25122?

Apache Tomcat versions 10.0.0-M1 to 10.0.0 and 9.0.0.M1 to 9.0.43 are affected by CVE-2021-25122.

3

How does CVE-2021-25122 affect Apache Tomcat?

CVE-2021-25122 allows user A and user B to see the results of user A's request due to duplicate request headers and a limited amount of request body.

4

What is the remedy for CVE-2021-25122 in Apache Tomcat 10.0.2?

The remedy for CVE-2021-25122 in Apache Tomcat 10.0.2 is to update to version 10.0.3.

5

Where can I find more information about CVE-2021-25122?

You can find more information about CVE-2021-25122 at the following references: [link1], [link2], [link3].

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