CVE-2021-33037

mediumpriority · attend · 47EPSS 0.747 · 99 %ileDEEUNLRUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

74.7% (99th) EPSS

CVSS 5 · medium

Is it mine?

133 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

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.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedtomcat-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-admin-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-admin-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-docs-webapp-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-docs-webapp-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-el-3_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-el-3_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-javadoc-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-javadoc-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-jsp-2_3-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-jsp-2_3-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-lib-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-lib-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-servlet-4_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-servlet-4_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedtomcat-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · OSV

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:Hsecondary · CVSS-BT (t0sche)

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · SUSE Product Security

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-444USprimaryCWE-444USCWE-444USCWE-444US

affected products (133)

Products and version ranges known to be affected.

Atlassian Bitbucket <10.0.2all versionscert_bundDE
Atlassian Bitbucket <8.19.25 (LTS)all versionscert_bundDE
Atlassian Bitbucket <9.4.13 (LTS)all versionscert_bundDE
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
EMC Avamarall versionscert_bundDEcpe:/a:emc:avamar:-
Hitachi Ops Centerall versionscert_bundDEcpe:/a:hitachi:ops_center:-
IBM Operational Decision Managerall versionscert_bundDEcpe:/a:ibm:operational_decision_manager:-
IBM QRadar SIEMall versionscert_bundDEcpe:/a:ibm:qradar_siem:-
IBM QRadar SIEM 7.4all versionscert_bundDEcpe:/a:ibm:qradar_siem:7.4
IBM QRadar SIEM 7.5all versionscert_bundDEcpe:/a:ibm:qradar_siem:7.5
IBM Spectrum Protect plus 10.1all versionscert_bundDEcpe:/a:ibm:spectrum_protect:plus_10.1
NetApp ActiveIQ Unified Managerall versionscert_bundDEcpe:/a:netapp:active_iq_unified_manager:-::~~~vmware_vsphere~~
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat FUSE <7.11.0all versionscert_bundDE
Red Hat JBoss Enterprise Application Platform <7.1.10all versionscert_bundDE
Red Hat JBoss Enterprise Application Platform <7.3.13all versionscert_bundDE
Atlassian Bitbucket< 10.0.2cert_bundDE
Atlassian Bitbucket< 8.19.25 (LTS)cert_bundDE
Atlassian Bitbucket< 9.4.13 (LTS)cert_bundDE
Red Hat Fuse< 7.11.0cert_bundDE

showing 20 of 133

advisories (10)

Vendor and ecosystem advisories describing this.

NCSC-2025-0123Kwetsbaarheden verholpen in Oracle Database ProductenNL2025-04-16csaf · ncsc_nlNL
Oracle heeft kwetsbaarheden verholpen in diverse Oracle Database Producten en subsystemen, zoals Oracle Server, NoSQL, TimesTen, Secure Backup en Essbase.
SUSE-SU-2026:1058-1Security update for tomcat2026-03-26csaf · suse_csafDE
Security update for tomcat
WID-SEC-W-2022-0607Red Hat FUSE: Mehrere SchwachstellenDeutsch2022-07-07csaf · cert_bundDE
Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Red Hat FUSE ausnutzen, um vertrauliche Informationen offenzulegen, beliebigen Code auszuführen, einen Denial of Service Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen, Daten und Informationen zu manipulieren und seine Privilegien zu erweitern.
WID-SEC-W-2022-1116Apache Tomcat: Mehrere SchwachstellenDeutsch2021-07-12csaf · cert_bundDE
Ein lokaler oder entfernter Angreifer kann mehrere Schwachstellen in Apache Tomcat ausnutzen, um einen Denial of Service Angriff durchzuführen oder Sicherheitsvorkehrungen zu umgehen.
WID-SEC-W-2022-1375JFrog Artifactory: Mehrere SchwachstellenDeutsch2022-09-11csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in JFrog Artifactory ausnutzen, um seine Privilegien zu erweitern, beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen und einen Denial-of-Service-Zustand auszulösen.
WID-SEC-W-2024-0528Dell Data Protection Advisor: Mehrere SchwachstellenDeutsch2024-02-29csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell Data Protection Advisor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand herbeizuführen, Dateien zu manipulieren, vertrauliche Informationen offenzulegen, seine Berechtigungen zu erweitern oder einen nicht spezifizierten Angriff durchzuführen.
WID-SEC-W-2024-1238HPE HP-UX: Mehrere SchwachstellenDeutsch2024-05-27csaf · cert_bundDE
Ein anonymer oder lokaler Angreifer kann mehrere Schwachstellen in HPE HP-UX Tomcat Servlet Engine ausnutzen, um Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand zu verursachen, vertrauliche Informationen offenzulegen oder Dateien zu manipulieren.
WID-SEC-W-2024-2180Oracle Fusion Middleware: Mehrere SchwachstellenDeutsch2022-04-19csaf · cert_bundDE
Ein entfernter, anonymer oder lokaler Angreifer kann mehrere Schwachstellen in Oracle Fusion Middleware ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
GHSA-4vww-mc66-62m6HTTP Request Smuggling in Apache Tomcat2021-08-13ghsa · osvUS
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.
BIT-tomcat-2021-33037Incorrect Transfer-Encoding handling with HTTP/1.02024-03-06vendor · osvUS
Apache Tomcat 10.0.0 to 10.0.6, 9.0.0 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.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund ncsc_nl suse_csaf NVD CVE.org MITRE

published 2021-07-12modified 2026-10-08

related (553)

Related entries.

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+548 more

references (78)

External citations — patches, advisories, analysis.

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