CVE-2021-28957

mediumPriorität · verfolgen · 25EPSS 0.040 · 91. PerzentilDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

4.04% (91st) EPSS

CVSS 4.3 · medium

Is it mine?

49 products

Prüfe deine Angriffsfläche

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · bewertet 2026-10-26

An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.

Behebungen

Hersteller-Fix, Mitigation oder Workaround, wie von den Quellen veröffentlicht.

Ein Hersteller-Fix ist verfügbar.

Behobenpython-lxml-0:4.2.3-3.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-2021:4158
Behobenpython-lxml-debugsource-0:4.2.3-3.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-2021:4158
Behobenpython-lxml-debugsource-0:4.2.3-3.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-2021:4158
Behobenpython-lxml-debugsource-0:4.2.3-3.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-2021:4158
Behobenpython-lxml-debugsource-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-debuginfo-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-debuginfo-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-debuginfo-0:4.2.3-3.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-2021:4158
Behobenpython3-lxml-debuginfo-0:4.2.3-3.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-2021:4158

cvss

Technischer Schweregrad, 0–10. Eine Zeile je Quelle.

6.1

010

Basiswert 0–10 · höher = schwerwiegender · Vektor überfahren zum Auflösen

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USAusnutzbarkeit 8.6 · Auswirkung 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 USAusnutzbarkeit 2.8 · Auswirkung 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:NsecondaryAusnutzbarkeit 2.8 · Auswirkung 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

Eine Handlungsentscheidung — aus Ausnutzung und Auswirkung.

Trackcoordinatorcisa_ssvcUS

schwächen

Die CWE-Schwächeklassen, zu denen dies gehört.

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

betroffene Produkte (49)

Betroffene Produkte und Versionsbereiche.

Amazon Linux 2alle Versionencert_bundDEcpe:/o:amazon:linux_2:-
Avaya Aura Experience Portalalle Versionencert_bundDEcpe:/a:avaya:aura_experience_portal:-
Debian Linuxalle Versionencert_bundDEcpe:/o:debian:debian_linux:-
Gentoo Linuxalle Versionencert_bundDEcpe:/o:gentoo:linux:-
IBM Security Verify Access 10.0.0-10.0.7.1alle Versionencert_bundDEcpe:/a:ibm:security_verify_access:10.0.0_-_10.0.7.1
Oracle Linuxalle Versionencert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxalle Versionencert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxalle Versionencert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat Enterprise Linux 8alle Versionencert_bundDEcpe:/o:redhat:enterprise_linux:8
Red Hat OpenShift Data Foundation <4.12.10alle Versionencert_bundDE
SUSE Linuxalle Versionencert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEalle Versionencert_bundDEcpe:/o:suse:opensuse:-
Ubuntu Linuxalle Versionencert_bundDEcpe:/o:canonical:ubuntu_linux:-
Red Hat OpenShift≤ Data Foundation <4.12.10cert_bundDE
n/a n/a≤ n/aenisa_euvdEU
Fedora Project Fedora≤ 33fstec_bduRU
Fedora Project Fedora≤ 34fstec_bduRU
Stefan Behnel Lxml≤ 4.6.3fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.1fstec_bduRU

20 von 49 angezeigt

Advisories (5)

Hersteller- und Ökosystem-Meldungen dazu.

RHSA-2021:4158Red Hat Security Advisory: python-lxml security update2021-11-09csaf · 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-2022-0571Red Hat Enterprise Linux: Mehrere SchwachstellenDeutsch2021-11-09csaf · cert_bundDE
Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux ausnutzen, um einen Cross-Site-Scripting-Angriff durchzuführen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen, beliebigen Code auszuführen, Dateien zu manipulieren und einen nicht spezifizierten Angriff durchzuführen.
WID-SEC-W-2023-0395Splunk Splunk Enterprise: Mehrere SchwachstellenDeutsch2023-02-14csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Splunk Splunk Enterprise ausnutzen, um vertrauliche Informationen offenzulegen, Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand zu verursachen, Daten zu manipulieren und einen Cross-Site-Scripting-Angriff durchzuführen.
GHSA-jq4v-f5q6-mjqqlxml vulnerable to Cross-Site Scripting 2021-03-22ghsa · osvUS
An XSS vulnerability was discovered in the python `lxml` clean module versions before 4.6.3. When disabling `the safe_attrs_only` and `forms` arguments, the `Cleaner` class does not remove the `formaction` attribute allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in `lxml` 4.6.3.
PYSEC-2021-192021-03-21vendor · osvUS
An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.

auch bekannt als (7)

Weitere Namen und Kennungen dieser Entität.

quellen

Welche Quellen diesen Datensatz belegen und wann.

cnnvd enisa_euvd fstec_bdu osv cert_bund redhat_csaf NVD CVE.org MITRE

veröffentlicht 2021-03-21geändert 2026-06-17

verwandt (52,974)

Verwandte Einträge.

ID	Schweregrad	EPSS	ausnutzbar	veröffentlicht
CVE-2026-42897US	medium6.1OT kritisch	70.7% (99th)	KEV	2026-05-14
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network…
CVE-2025-66376US	medium6.1OT kritisch	20.2% (97th)	KEV	2026-01-05
Zimbra Collaboration (ZCS) 10 before 10.0.18 and 10.1 before 10.1.13 allows Classic UI stored XSS via Cascading Style Sheets (CSS) @import directives in an HTML e-mail message.
CVE-2025-68461US	medium6.1OT kritisch	27.4% (98th)	KEV	2025-12-18
Roundcube Webmail before 1.5.12 and 1.6 before 1.6.12 is prone to a Cross-Site-Scripting (XSS) vulnerability via the animate tag in an SVG document.
CVE-2025-48700US	—OT kritisch	1.71% (77th)	KEV	2025-06-23
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to exec…
CVE-2025-27915US	—OT kritisch	4.06% (91st)	KEV	2025-03-12
An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient…

+52969 weitere

Referenzen (49)

Externe Belege — Patches, Meldungen, Analysen.

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