CVE catalog
CVE-2021-33037
Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request
- Severity
- Medium · CVSS 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 74.67% · Oct 27, 2026
Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request smuggling when used with a reverse proxy. Specifically: - Tomcat incorrectly ignored the transfer encoding header if the client declared it would only accept an HTTP/1.0 response; - Tomcat honoured the identify encoding; and - Tomcat did not ensure that, if present, the chunked encoding was the final encoding.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | tomcat9 | sid | 9.0.122-1 | fixed |
| Debian | tomcat9 | forky | 9.0.122-1 | fixed |
| Debian | tomcat9 | trixie | 9.0.95-1 | fixed |
| Debian | tomcat9 | bookworm | 9.0.70-2 | fixed |
| Cpe | tomcat | Not reported | Not reported | unknown |
| Cpe | tomcat | Not reported | Not reported | unknown |
| Cpe | tomee | Not reported | Not reported | unknown |
| Cpe | debian_linux | Not reported | Not reported | unknown |
| Cpe | agile_product_lifecycle_management | Not reported | Not reported | unknown |
| Cpe | communications_cloud_native_core_policy | Not reported | Not reported | unknown |
| Cpe | communications_cloud_native_core_service_communication_proxy | Not reported | Not reported | unknown |
| Cpe | communications_diameter_signaling_router | Not reported | Not reported | unknown |
| Cpe | communications_instant_messaging_server | Not reported | Not reported | unknown |
| Cpe | communications_policy_management | Not reported | Not reported | unknown |
| Cpe | communications_pricing_design_center | Not reported | Not reported | unknown |
| Cpe | communications_session_report_manager | Not reported | Not reported | unknown |
| Cpe | communications_session_route_manager | Not reported | Not reported | unknown |
| Cpe | graph_server_and_client | Not reported | 21.4 | fixed |
| Cpe | healthcare_translational_research | Not reported | Not reported | unknown |
| Cpe | hospitality_cruise_shipboard_property_management_system | Not reported | Not reported | unknown |
| Cpe | instantis_enterprisetrack | Not reported | Not reported | unknown |
| Ubuntu | tomcat6 | pro | 6.0.37-1 | vulnerable |
| Ubuntu | tomcat6 | pro | 6.0.39-1 | vulnerable |
| Ubuntu | tomcat6 | pro | 6.0.39-1ubuntu0.1 | vulnerable |
| Ubuntu | tomcat6 | pro | 6.0.39-1ubuntu0.1+esm1 | vulnerable |
| Ubuntu | tomcat6 | pro | 6.0.39-1ubuntu0.1+esm2 | vulnerable |
| Ubuntu | tomcat6 | pro | 6.0.39-1ubuntu0.1+esm3 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.64-1 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.1 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.3 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.4 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.4+esm1 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.4+esm2 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.4+esm3 | vulnerable |
| Ubuntu | tomcat7 | pro | 7.0.68-1ubuntu0.4+esm4 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.21-1ubuntu1 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.29-1 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.30-1 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.30-1ubuntu1 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.30-1ubuntu1.2 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.30-1ubuntu1.3 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.30-1ubuntu1.4 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.1 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.2 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3+esm1 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3+esm2 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3+esm3 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3+esm4 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3+esm5 | vulnerable |
| Ubuntu | tomcat8 | pro | 8.5.39-1ubuntu1~18.04.3+esm6 | vulnerable |
| Ubuntu | tomcat9 | 18.04 | 9.0.16-3~18.04.1 | vulnerable |
| Ubuntu | tomcat9 | 18.04 | 9.0.16-3ubuntu0.18.04.1 | vulnerable |
| Ubuntu | tomcat9 | 18.04 | 9.0.16-3ubuntu0.18.04.2 | fixed |
| Ubuntu | tomcat9 | 20.04 | 9.0.24-1 | vulnerable |
| Ubuntu | tomcat9 | 20.04 | 9.0.27-1 | vulnerable |
| Ubuntu | tomcat9 | 20.04 | 9.0.31-1 | vulnerable |
| Ubuntu | tomcat9 | 20.04 | 9.0.31-1ubuntu0.1 | vulnerable |
| Ubuntu | tomcat9 | 20.04 | 9.0.31-1ubuntu0.2 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | tomcat9 | source | sid | 9.0.43-2 | not yet assigned | Not reported | [991046] |
| Debian | tomcat9 | source | forky | 9.0.43-2 | not yet assigned | Not reported | [991046] |
| Debian | tomcat9 | source | trixie | 9.0.43-2 | not yet assigned | Not reported | [991046] |
| Debian | tomcat9 | source | bookworm | 9.0.43-2 | not yet assigned | Not reported | [991046] |
| Cpe | graph_server_and_client | cpe | Not reported | 21.4 | Not reported | NVD-CVE-2021-33037 | Not reported |
| Ubuntu | tomcat9 | deb | 18.04 | 9.0.16-3ubuntu0.18.04.2 | Not reported | UBUNTU-CVE-2021-33037 | Not reported |
| Ubuntu | tomcat9 | deb | 20.04 | 9.0.31-1ubuntu0.2 | Not reported | UBUNTU-CVE-2021-33037 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libtomcat9-java]Fixed
Source package: [tomcat9]
Details (2)
9.0.70-2· all · bookwormFixed · Fixed:
9.0.43-2nvd · tomcat9 · debian · bookworm; nvd · tomcat9 · debian · 12
9.0.70-2· all · bookwormFixed · Fixed:
9.0.43-2nvd · tomcat9 · debian · bookworm; nvd · tomcat9 · debian · 12
[Debian 13 (Trixie)]
- [libtomcat9-java]Fixed
Source package: [tomcat9]
Details (2)
9.0.95-1· all · trixieFixed · Fixed:
9.0.43-2nvd · tomcat9 · debian · 13
9.0.95-1· all · trixieFixed · Fixed:
9.0.43-2nvd · tomcat9 · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2026_1058-1.json]
- [https://nvd.nist.gov/vuln/detail/CVE-2021-33037]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2021-33037]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2021-33037]
- [https://security-tracker.debian.org/tracker/CVE-2021-33037]
- [https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-33037.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2021/wid-sec-w-2022-1116.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]