CVE-2020-13943

mediumpriority · track · 36EPSS 0.550 · 99 %ileDEEUNLUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

55.0% (99th) EPSS

CVSS 4 · medium

Is it mine?

229 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-22

If an HTTP/2 client connecting to Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37 or 8.5.0 to 8.5.57 exceeded the agreed maximum number of concurrent streams for a connection (in violation of the HTTP/2 protocol), it was possible that a subsequent request made on that connection could contain HTTP headers - including HTTP/2 pseudo headers - from a previous request rather than the intended headers. This could lead to users seeing responses for unexpected resources.

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 · 4–7.5

v2.04mediumAV:N/AC:L/Au:S/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 8 · impact 2.9

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 1.4

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Nsecondary · OSV

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:Hsecondary · CVSS-BT (t0sche)

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

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-200USCWE-200US

affected products (229)

Products and version ranges known to be affected.

IBM QRadar SIEMall versionscert_bundDEcpe:/a:ibm:qradar_siem:-
IBM QRadar SIEM <7.3.3 Patch 7all versionscert_bundDE
IBM QRadar SIEM <7.4.2 Patch 2all versionscert_bundDE
IBM QRadar SIEM< 7.3.3 Patch 7cert_bundDE
IBM QRadar SIEM< 7.4.2 Patch 2cert_bundDE
n/a Apache Tomcat≤ Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37, 8.5.0 to 8.5.57enisa_euvdEU
Autonomous Health Framework≤ vers:oracle/>=23.8.0|<=23.11.0ncsc_nlNLcpe:2.3:a:oracle:autonomous_health_framework:23.8.0-23.11.0:*:*:*:*:*:*:*
Autonomous Health Framework≤ vers:oracle/>=24.1.0|<=24.11.0ncsc_nlNLcpe:2.3:a:oracle:autonomous_health_framework:24.1.0-24.11.0:*:*:*:*:*:*:*
Autonomous Health Framework≤ vers:oracle/25.2.0ncsc_nlNLcpe:2.3:a:oracle:autonomous_health_framework:25.2.0:*:*:*:*:*:*:*
Autonomous Health Framework≤ vers:oracle/25.1.0ncsc_nlNLcpe:2.3:a:oracle:autonomous_health_framework:25.1.0:*:*:*:*:*:*:*
Big Data Spatial and Graph≤ vers:unknown/2.0ncsc_nlNLcpe:2.3:a:ibm:oracle_big_data_spatial_and_graph:2.0:*:*:*:*:*:*:*
GoldenGate Stream Analytics≤ vers:oracle/>=19.1.0.0.0|<=19.1.0.0.10ncsc_nlNLcpe:2.3:a:oracle:goldengate_stream_analytics:19.1.0.0.0-19.1.0.0.10:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/24.3.0ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:24.3.0:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/<=22.4.7ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:22.4.7_and_prior:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/24.4.0ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:24.4.0:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/23.4.3ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:23.4.3:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/23.4.4ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:23.4.4:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/<=23.4.2ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:23.4.2_and_prior:*:*:*:*:*:*:*
Graph Server and Client≤ vers:oracle/<=24.1.0ncsc_nlNLcpe:2.3:a:oracle:graph_server_and_client:24.1.0_and_prior:*:*:*:*:*:*:*
Oracle Big Data Spatial and Graph≤ vers:oracle/3.0.6ncsc_nlNLcpe:2.3:a:oracle:big_data_spatial_and_graph:3.0.6:*:*:*:*:*:*:*

showing 20 of 229

advisories (7)

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-2023-2467Apache Tomcat: Schwachstelle ermöglicht Offenlegung von InformationenDeutsch2020-10-11csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Apache Tomcat ausnutzen, um Informationen offenzulegen.
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-2026-3721IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2021-05-04csaf · cert_bundDE
Ein entfernter, anonymer, authentifizierter, lokaler oder benachbarter Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um Informationen offenzulegen, Cross-Site-Scripting-Angriffe durchzuführen, Sicherheitsmaßnahmen zu umgehen, beliebigen Code auszuführen oder einen Denial of Service Zustand auszulösen.
GHSA-f268-65qc-98vgExposure of Sensitive Information to an Unauthorized Actor in Apache Tomcat2022-02-09ghsa · osvUS
If an HTTP/2 client connecting to Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37 or 8.5.0 to 8.5.57 exceeded the agreed maximum number of concurrent streams for a connection (in violation of the HTTP/2 protocol), it was possible that a subsequent request made on that connection could contain HTTP headers - including HTTP/2 pseudo headers - from a previous request rather than the intended headers. This could lead to users seeing responses for unexpected resources.
BIT-tomcat-2020-139432024-03-06vendor · osvUS
If an HTTP/2 client connecting to Apache Tomcat 9.0.0 through 9.0.37 or 8.5.0 to 8.5.57 exceeded the agreed maximum number of concurrent streams for a connection (in violation of the HTTP/2 protocol), it was possible that a subsequent request made on that connection could contain HTTP headers - including HTTP/2 pseudo headers - from a previous request rather than the intended headers. This could lead to users seeing responses for unexpected resources.

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund ncsc_nl suse_csaf NVD CVE.org MITRE

published 2020-10-12modified 2026-06-17

references (45)

External citations — patches, advisories, analysis.

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