Apache Tomcat: Information disclosure
Priority LOW 22CWE-362Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Partial Red Hat: 4 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA, GitHub and Red Hat.
Summary
The simplified implementation of blocking reads and writes introduced in Tomcat 10 and back-ported to Tomcat 9.0.47 onwards exposed a long standing (but extremely hard to trigger) concurrency bug in Apache Tomcat 10.1.0 to 10.1.0-M12, 10.0.0-M1 to 10.0.18, 9.0.0-M1 to 9.0.60 and 8.5.0 to 8.5.77 that could cause client connections to share an Http11Processor instance resulting in responses, or part responses, to be received by the wrong client.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02362 83rd percentileScored 2026-11-07
Fix Partial org.apache.tomcat:tomcat (Maven): 8.5.78, 9.0.62, 10.0.20 +1Red Hat: 2 advisoriesRed Hat: 4 fixed, 2 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Apache | Apache Tomcat | 10.1.0-M1 to 10.1.0-M12; 10.0.0-M1 to 10.0.18; 9.0.0-M1 to 9.0.60; 8.5.0 to 8.5.77 | — | No fix listed | CNA |
| — | org.apache.tomcat:tomcat (Maven) | 8.5.0 to before 8.5.78 | 8.5.78 | Patch available | GHSA-jx7c-7mj5-9438 |
| — | org.apache.tomcat:tomcat (Maven) | 9.0.0-M1 to before 9.0.62 | 9.0.62 | Patch available | GHSA-jx7c-7mj5-9438 |
| — | org.apache.tomcat:tomcat (Maven) | 10.0.0-M1 to before 10.0.20 | 10.0.20 | Patch available | GHSA-jx7c-7mj5-9438 |
| — | org.apache.tomcat:tomcat (Maven) | 10.1.0-M1 to before 10.1.0-M14 | 10.1.0-M14 | Patch available | GHSA-jx7c-7mj5-9438 |
- Apache Tomcat VendorApache Affected 10.1.0-M1 to 10.1.0-M12; 10.0.0-M1 to 10.0.18; 9.0.0-M1 to 9.0.60; 8.5.0 to 8.5.77 Fixed in — No fix listed CNA
- org.apache.tomcat:tomcat (Maven) Vendor— Affected 8.5.0 to before 8.5.78 Fixed in 8.5.78 Patch available GHSA-jx7c-7mj5-9438
- org.apache.tomcat:tomcat (Maven) Vendor— Affected 9.0.0-M1 to before 9.0.62 Fixed in 9.0.62 Patch available GHSA-jx7c-7mj5-9438
- org.apache.tomcat:tomcat (Maven) Vendor— Affected 10.0.0-M1 to before 10.0.20 Fixed in 10.0.20 Patch available GHSA-jx7c-7mj5-9438
- org.apache.tomcat:tomcat (Maven) Vendor— Affected 10.1.0-M1 to before 10.1.0-M14 Fixed in 10.1.0-M14 Patch available GHSA-jx7c-7mj5-9438
CPE configurations NVD · 15
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:* | 8.5.0 – 8.5.77; 9.0.0 – 9.0.60; 10.0.0 – 10.0.18 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone1:*:*:*:*:*:* | 10.1.0 milestone1 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone10:*:*:*:*:*:* | 10.1.0 milestone10 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone11:*:*:*:*:*:* | 10.1.0 milestone11 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone12:*:*:*:*:*:* | 10.1.0 milestone12 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone2:*:*:*:*:*:* | 10.1.0 milestone2 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone3:*:*:*:*:*:* | 10.1.0 milestone3 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone4:*:*:*:*:*:* | 10.1.0 milestone4 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone5:*:*:*:*:*:* | 10.1.0 milestone5 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone6:*:*:*:*:*:* | 10.1.0 milestone6 | Vulnerable | Apache |
- cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:* Versions 8.5.0 – 8.5.77; 9.0.0 – 9.0.60; 10.0.0 – 10.0.18 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone1:*:*:*:*:*:* Versions 10.1.0 milestone1 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone10:*:*:*:*:*:* Versions 10.1.0 milestone10 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone11:*:*:*:*:*:* Versions 10.1.0 milestone11 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone12:*:*:*:*:*:* Versions 10.1.0 milestone12 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone2:*:*:*:*:*:* Versions 10.1.0 milestone2 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone3:*:*:*:*:*:* Versions 10.1.0 milestone3 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone4:*:*:*:*:*:* Versions 10.1.0 milestone4 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone5:*:*:*:*:*:* Versions 10.1.0 milestone5 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone6:*:*:*:*:*:* Versions 10.1.0 milestone6 Vulnerable ·Apache
Show 5 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:apache:tomcat:10.1.0:milestone7:*:*:*:*:*:* | 10.1.0 milestone7 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone8:*:*:*:*:*:* | 10.1.0 milestone8 | Vulnerable | Apache |
| cpe:2.3:a:apache:tomcat:10.1.0:milestone9:*:*:*:*:*:* | 10.1.0 milestone9 | Vulnerable | Apache |
| cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* | 11.0 | Vulnerable | Debian |
- cpe:2.3:a:apache:tomcat:10.1.0:milestone7:*:*:*:*:*:* Versions 10.1.0 milestone7 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone8:*:*:*:*:*:* Versions 10.1.0 milestone8 Vulnerable ·Apache
- cpe:2.3:a:apache:tomcat:10.1.0:milestone9:*:*:*:*:*:* Versions 10.1.0 milestone9 Vulnerable ·Apache
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian
Remediation
- Fix · GHSA-jx7c-7mj5-9438 org.apache.tomcat:tomcat (Maven) Fixed in 8.5.78 Advisory →
- Fix · GHSA-jx7c-7mj5-9438 org.apache.tomcat:tomcat (Maven) Fixed in 9.0.62 Advisory →
- Fix · GHSA-jx7c-7mj5-9438 org.apache.tomcat:tomcat (Maven) Fixed in 10.0.20 Advisory →
- Fix · GHSA-jx7c-7mj5-9438 org.apache.tomcat:tomcat (Maven) Fixed in 10.1.0-M14 Advisory →
Red Hat 2 advisories
- RHSA-2022:7272 Released 2022-11-02 · Red Hat rating ModerateRed Hat JBoss Web Server 5.7.0 release and security update
- Red Hat JBoss Web Server 5.7 for RHEL 7 Server jws5-ecj-4.20.0-1.redhat_00002.1.el7jws, jws5-tomcat-9.0.62-9.redhat_00005.1.el7jws, jws5-tomcat-admin-webapps-9.0.62-9.redhat_00005.1.el7jws +11
- Red Hat JBoss Web Server 5.7 for RHEL 8 jws5-ecj-4.20.0-1.redhat_00002.1.el8jws, jws5-tomcat-9.0.62-9.redhat_00005.1.el8jws, jws5-tomcat-admin-webapps-9.0.62-9.redhat_00005.1.el8jws +9
- Red Hat JBoss Web Server 5.7 for RHEL 9 jws5-1-8.el9jws, jws5-ecj-4.20.0-1.redhat_00002.1.el9jws, jws5-javapackages-tools-3.4.1-5.15.11.el9jws +18
- RHSA-2022:7273 Released 2022-11-02 · Red Hat rating ModerateRed Hat JBoss Web Server 5.7.0 release and security update
- JWS 5.7.0
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| JWS 5.7.0 | Fixed | RHSA-2022:7273 |
| Red Hat JBoss Web Server 5.7 for RHEL 7 Server | Fixed | RHSA-2022:7272 |
| Red Hat JBoss Web Server 5.7 for RHEL 8 | Fixed | RHSA-2022:7272 |
| Red Hat JBoss Web Server 5.7 for RHEL 9 | Fixed | RHSA-2022:7272 |
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat JBoss Web Server 3
Timeline
- 2026-10-02 Threatist record created from CVE-2021-43980
- 2026-10-03 Alias added: GHSA-jx7c-7mj5-9438
References
Advisory 5
Other 8
- https://github.com/apache/tomcat/commit/170e0f792bd18ff031677890ba2fe50eb7a376c1
- https://github.com/apache/tomcat/commit/17f177eeb7df5938f67ef9ea580411b120195f13
- https://github.com/apache/tomcat/commit/4a00b0c0890538b9d3107eef8f2e0afadd119beb
- https://github.com/apache/tomcat/commit/9651b83a1d04583791525e5f0c4c9089f678d9fc
- https://github.com/apache/tomcat
- https://tomcat.apache.org/security-10.html
- https://tomcat.apache.org/security-8.html
- https://tomcat.apache.org/security-9.html
More Apache Tomcat vulnerabilities
- TI-2025-18529 Apache Tomcat: Potential RCE and/or information disclosure and/or information corruption with partial PUT KEVCVSS 3.1CRITICAL 10.0
- TI-2020-01862 Improper privilege management in Apache Tomcat KEVCVSS 3.1CRITICAL 9.8
- TI-2016-07192 Improper access control in Apache Tomcat KEVCVSS 3.1CRITICAL 9.8
- TI-2017-09342 Unrestricted file upload in Apache Tomcat KEVCVSS 3.1HIGH 8.1
- TI-2017-09340 Unrestricted file upload in Apache Tomcat KEVCVSS 3.1HIGH 8.1
- TI-2026-26741 Apache Tomcat: Fix for CVE-2026-29146 allowed bypass of EncryptInterceptor KEVCVSS 3.1HIGH 7.5
Sources
- CVE-2021-43980 · CVE Program
- CVE-2021-43980 · NVD
- FIRST EPSS
- GHSA-jx7c-7mj5-9438 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-43980 · Red Hat security data · CC BY 4.0
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