CVE-2021-22959

mediumpriority · track · 27EPSS 0.032 · 88 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
3.16% (88th) EPSS
CVSS 6.4 · medium
Is it mine?
34 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-26

The parser in accepts requests with a space (SP) right after the header name before the colon. This can lead to HTTP Request Smuggling (HRS) in llhttp < v2.1.4 and < v6.0.6.

01

remediations

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

A vendor fix is available.

  • Fixedfesto_psirt

    FactoryViews (non-Lite): Upgrade to FactoryViews 1.6.0. See the upgrade guide for information on how to upgrade. FactoryViews Lite: Upgrade to FactoryViews 1.7.0. See the upgrade guide for information on how to upgrade.

02

cvss

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

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6–9.8

v2.06.4mediumAV:N/AC:L/Au:N/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 10 · impact 4.9
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 2.5
v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nsecondary · Festo PSIRT DE
v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-444USprimaryCWE-444USCWE-444US
04

affected products (34)

Products and version ranges known to be affected.

showing 20 of 34
05

advisories (4)

Vendor and ecosystem advisories describing this.

  • FSA-202302Festo: Several vulnerabilities in FactoryViews2023-07-10csaf · festo_psirtDE

    FactoryViews bundles many third-party applications which are used in background processes to provide the software's features. From time to time, vulnerabilities in these bundled applications are discovered. These are typically fixed in newer versions of FactoryViews by updating the bundled applications. FactoryViews versions up to and including 1.5.2 contain around 200 such vulnerabilities listed in this advisory.Version 1.6.0 is a security rollup release which includes updates to all bundled applications and fixes these vulnerabilities. At this time, FactoryViews Lite cannot be updated beyond version 1.1. FactoryViews 1.7 unifies the non-Lite and Lite versions and fixes these vulnerabilities for users of FactoryViews Lite.

  • WID-SEC-W-2022-0093Node.js: Mehrere Schwachstellen ermöglichen "HTTP request smuggling"Deutsch2021-10-12csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Node.js ausnutzen, um einen "HTTP request smuggling" Angriff durchzuführen.

  • WID-SEC-W-2022-0100Oracle Java SE und OpenJDK: Mehrere SchwachstellenDeutsch2022-01-18csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Oracle Java SE und OpenJDK ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

  • WID-SEC-W-2025-2471IBM Spectrum Protect Plus: Mehrere SchwachstellenDeutsch2022-01-31csaf · cert_bundDE

    Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in IBM Spectrum Protect ausnutzen, um Daten zu manipulieren, Sicherheitsmaßnahmen zu umgehen und beliebigen Code auszuführen.

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundfesto_psirtNVDCVE.orgMITRE
published 2021-11-15modified 2026-06-17
09

references (35)

External citations — patches, advisories, analysis.

scry

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