CVE-2020-27783

mediumpriority · track · 25EPSS 0.040 · 90 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

3.98% (90th) EPSS

CVSS 4.3 · medium

Is it mine?

42 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

A XSS vulnerability was discovered in python-lxml's clean module. The module's parser didn't properly imitate browsers, which caused different behaviors between the sanitizer and the user's page. A remote attacker could exploit this flaw to run arbitrary HTML/JS code.

remediations

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

A vendor fix is available.

Fixedpython-lxml-0:4.2.3-2.el8.src as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython-lxml-debugsource-0:4.2.3-2.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython-lxml-debugsource-0:4.2.3-2.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython-lxml-debugsource-0:4.2.3-2.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython-lxml-debugsource-0:4.2.3-2.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-0:4.2.3-2.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-0:4.2.3-2.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-0:4.2.3-2.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-0:4.2.3-2.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-debuginfo-0:4.2.3-2.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-debuginfo-0:4.2.3-2.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-debuginfo-0:4.2.3-2.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898
Fixedpython3-lxml-debuginfo-0:4.2.3-2.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:1898

cvss

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

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.16.1mediumAV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · ENISA EU

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondaryexploitability 2.8 · impact 2.7

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · OSV

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · Red Hat Product Security US

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USCWE-79USCWE-79USCWE-79US

affected products (42)

Products and version ranges known to be affected.

IBM QRadar SIEM 7.5.0all versionscert_bundDEcpe:/a:ibm:qradar_siem:7.5.0
IBM QRadar SIEM <7.5.0 UP11 IF01all versionscert_bundDE
IBM QRadar SIEM <7.5.0 UP8 IF02all versionscert_bundDE
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
IBM QRadar SIEM< 7.5.0 UP11 IF01cert_bundDE
IBM QRadar SIEM< 7.5.0 UP8 IF02cert_bundDE
n/a python-lxml≤ lxml-4.6.2enisa_euvdEU
Stefan Behnel Lxml1.2 → 4.6.2fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.1fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Common Edition≤ 2.12 «Орёл»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU
ООО «РусБИТех-Астра» ПК «ALD Pro»≤ 2.4.2fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 8fstec_bduRU
debian debian linux= 10.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
fedoraproject fedora= 32nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*

showing 20 of 42

advisories (5)

Vendor and ecosystem advisories describing this.

RHSA-2021:1898Red Hat Security Advisory: python-lxml security update2021-05-18csaf · redhat_csafUS
An update for python-lxml is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
WID-SEC-W-2022-0931Red Hat Enterprise Linux (python-lxml): Schwachstelle ermöglicht Cross-Site ScriptingDeutsch2021-05-18csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Red Hat Enterprise Linux im python-lxml Modul ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen.
WID-SEC-W-2024-1086IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2024-05-09csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand herbeizuführen, vertrauliche Informationen offenzulegen, Dateien zu manipulieren, seine Privilegien zu erweitern, einen Cross-Site-Scripting (XSS)-Angriff durchzuführen oder einen nicht spezifizierten Angriff auszuführen.
GHSA-pgww-xf46-h92rlxml vulnerable to Cross-site Scripting2021-01-07ghsa · osvUS
A XSS vulnerability was discovered in python-lxml's clean module. The module's parser didn't properly imitate browsers, which caused different behaviors between the sanitizer and the user's page. A remote attacker could exploit this flaw to run arbitrary HTML/JS code.
PYSEC-2020-622020-12-03vendor · osvUS
A XSS vulnerability was discovered in python-lxml's clean module. The module's parser didn't properly imitate browsers, which caused different behaviors between the sanitizer and the user's page. A remote attacker could exploit this flaw to run arbitrary HTML/JS code.

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund nvd redhat_csaf NVD CVE.org MITRE

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

references (46)

External citations — patches, advisories, analysis.

scry

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