CVE-2020-27782

highpriority · track · 30EPSS 0.014 · 72 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.38% (72nd) EPSS

CVSS 7.8 · high

Is it mine?

16 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

A flaw was found in the Undertow AJP connector. Malicious requests and abrupt connection closes could be triggered by an attacker using query strings with non-RFC compliant characters resulting in a denial of service. The highest threat from this vulnerability is to system availability. This affects Undertow 2.1.5.SP1, 2.0.33.SP2, and 2.2.3.SP1.

cvss

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

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

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

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

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USCWE-400US

affected products (16)

Products and version ranges known to be affected.

Hitachi Ops Centerall versionscert_bundDEcpe:/a:hitachi:ops_center:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat JBoss Enterprise Application Platform <7.3.5all versionscert_bundDE
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Red Hat JBoss Enterprise Application Platform< 7.3.5cert_bundDE
n/a undertow≤ 2.0.33.SP2enisa_euvdEU
n/a undertow≤ 2.1.5.SP1enisa_euvdEU
n/a undertow≤ 2.2.3.SP1enisa_euvdEU
redhat jboss fuse= 6.0.0nvdUScpe:2.3:a:redhat:jboss_fuse:*:*:*:*:*:*:*:*
redhat jboss fuse= 7.0.0nvdUScpe:2.3:a:redhat:jboss_fuse:*:*:*:*:*:*:*:*
redhat openshift application runtimesall versionsnvdUScpe:2.3:a:redhat:openshift_application_runtimes:*:*:*:*:*:*:*:*
redhat undertow= 2.0.33nvdUScpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
redhat undertow= 2.1.5nvdUScpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
redhat undertow= 2.2.3nvdUScpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
Maven io.undertow:undertow-core< 2.0.33osvUSpkg:maven/io.undertow/undertow-core
Maven io.undertow:undertow-core2.1.0 → 2.1.5osvUSpkg:maven/io.undertow/undertow-core

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1273Red Hat JBoss Enterprise Application Platform: Mehrere SchwachstellenDeutsch2021-01-25csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Red Hat JBoss Enterprise Application Platform ausnutzen, um Informationen offenzulegen und um einen Denial of Service zu verursachen.
GHSA-rhcw-wjcm-9h6gDenial of service in Undertow2022-02-09ghsa · osvUS
A flaw was found in the Undertow AJP connector. Malicious requests and abrupt connection closes could be triggered by an attacker using query strings with non-RFC compliant characters resulting in a denial of service. The highest threat from this vulnerability is to system availability. This affects Undertow 2.1.5.SP1, 2.0.33.SP2, and 2.2.3.SP1.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd osv NVD CVE.org MITRE

published 2021-02-23modified 2026-06-17

references (19)

External citations — patches, advisories, analysis.

scry

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