CVE-2020-17527

mediumpriority · attend · 49EPSS 0.246 · 98 %ileexploit · PoCDEEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

24.6% (98th) EPSS

CVSS 5 · medium

Is it mine?

49 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

While investigating bug 64830 it was discovered that Apache Tomcat 10.0.0-M1 to 10.0.0-M9, 9.0.0-M1 to 9.0.39 and 8.5.0 to 8.5.59 could re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. While this would most likely lead to an error and the closure of the HTTP/2 connection, it is possible that information could leak between requests.

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 · 5–7.5

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

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · OSV

v3.17.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Psecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · SUSE Product Security

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-200USprimaryCWE-200US

exploits (1)

Public proof-of-concept and weaponised exploit code.

forse01/CVE-2020-17527-Tomcatforse01/CVE-2020-17527-TomcatPoC · poc_in_github

affected products (49)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Apache Tomcat <10.0.0-M10all versionscert_bundDE
Apache Tomcat <8.5.60all versionscert_bundDE
Apache Tomcat <9.0.40all versionscert_bundDE
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Dell Data Protection Advisor <19.12all versionscert_bundDE
F5 BIG-IPall versionscert_bundDEcpe:/a:f5:big-ip:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Open Source Arch Linuxall versionscert_bundDEcpe:/o:archlinux:archlinux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Apache Tomcat< 10.0.0-M10cert_bundDE
Apache Tomcat< 8.5.60cert_bundDE
Apache Tomcat< 9.0.40cert_bundDE
Dell Data Protection Advisor< 19.12cert_bundDE
Apache Software Foundation Apache Tomcat≤ Apache Tomcat 10 10.0.0-M1 to 10.0.0-M9enisa_euvdEU
Apache Software Foundation Apache Tomcat≤ Apache Tomcat 9 9.0.0-M1 to 9.0.39enisa_euvdEU
Apache Software Foundation Apache Tomcat≤ Apache Tomcat 8.5 8.5.0 to 8.5.59enisa_euvdEU
apache tomcat= 10.0.0nvdUScpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*

showing 20 of 49

advisories (5)

Vendor and ecosystem advisories describing this.

SUSE-SU-2026:1058-1Security update for tomcat2026-03-26csaf · suse_csafDE
Security update for tomcat
WID-SEC-W-2023-0065Oracle MySQL: Mehrere SchwachstellenDeutsch2021-04-20csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Oracle MySQL ausnutzen, um die Verfügbarkeit, Vertraulichkeit und Integrität zu gefährden.
WID-SEC-W-2023-2466Apache Tomcat: Schwachstelle ermöglicht Offenlegung von InformationenDeutsch2020-12-03csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Apache Tomcat ausnutzen, um Informationen offenzulegen.
GHSA-vvw4-rfwf-p6hxExposure of Sensitive Information to an Unauthorized Actor in Apache Tomcat2022-02-09ghsa · osvUS
While investigating bug 64830 it was discovered that Apache Tomcat 10.0.0-M1 to 10.0.0-M9, 9.0.0-M1 to 9.0.39 and 8.5.0 to 8.5.59 could re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. While this would most likely lead to an error and the closure of the HTTP/2 connection, it is possible that information could leak between requests.
BIT-tomcat-2020-17527Apache Tomcat: Request header mix-up between HTTP/2 streams2024-03-06vendor · osvUS
While investigating bug 64830 it was discovered that Apache Tomcat 9.0.0 through 9.0.39 and 8.5.0 to 8.5.59 could re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. While this would most likely lead to an error and the closure of the HTTP/2 connection, it is possible that information could leak between requests.

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 nvd suse_csaf NVD CVE.org MITRE

published 2020-12-03modified 2026-06-17

related (19,389)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-20133US	high7.5OT critical	31.5% (98th)	KEV	2026-02-25
A vulnerability in Cisco Catalyst SD-WAN Software could allow an unauthenticated, remote attacker to view sensitive information on an affected system. This vulnerability is due…
CVE-2026-20128US	—OT critical	7.32% (94th)	KEV	2026-02-25
A vulnerability in the Data Collection Agent (DCA) feature of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain DCA user privileges on an affect…
CVE-2026-20122US	medium5.4OT critical	25.8% (98th)	KEV	2026-02-25
A vulnerability in the API of Cisco Catalyst SD-WAN Manager could allow an authenticated, remote attacker to overwrite arbitrary files on the local file system. To exploit this vul…
CVE-2025-68686US	—OT critical	29.5% (98th)	KEV	2026-02-10
An Exposure of Sensitive Information to an Unauthorized Actor vulnerability [CWE-200] vulnerability in Fortinet FortiOS 7.6.0 through 7.6.1, FortiOS 7.4.0 through 7.4.6, FortiOS 7.…
CVE-2026-20805US	—OT critical	7.46% (94th)	KEV	2026-01-13
Exposure of sensitive information to an unauthorized actor in Desktop Windows Manager allows an authorized attacker to disclose information locally.

+19384 more

references (105)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan