BlackTreeCVE Intelligence
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Full vulnerability report · 2021
CVE-2021-23368High confidence

Regular Expression Denial of Service (ReDoS)

Unknown · postcss

5.3MediumCVSS 3.1
Recommended action
Within 7 days

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:High, raised one band.upgradedsince 16 Sep 2024

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • A structured source references public exploit or proof-of-concept material.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 3.51% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Unknown postcss and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 30 daysRemediation target: Within 180 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-specific package status

Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

4 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcenode-postcssVendor fix publishedDebian records a fixed source-package version for this release.8.2.1+~cs5.3.23-6Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcenode-postcssVendor fix publishedDebian records a fixed source-package version for this release.8.2.1+~cs5.3.23-6Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcenode-postcssVendor fix publishedDebian records a fixed source-package version for this release.8.2.1+~cs5.3.23-6Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcenode-postcssVendor fix publishedDebian records a fixed source-package version for this release.8.2.1+~cs5.3.23-6Debian Security Tracker ↗Source updated 5 Oct 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-1108

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

The package postcss from 7.0.0 and before 8.2.10 are vulnerable to Regular Expression Denial of Service (ReDoS) during source map parsing.

What

The package postcss from 7.0.0 and before 8.2.10 are vulnerable to Regular Expression Denial of Service (ReDoS) during source map parsing.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

What

The package postcss from 7.0.0 and before 8.2.10 are vulnerable to Regular Expression Denial of Service (ReDoS) during source map parsing.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
a network path → vulnerable operation → disrupt the affected service
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.ALowAvailability impact: A successful attack can cause a limited loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedDenial of servicePublic exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2023-0809IBM QRadar SIEM: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um beliebigen Programmcode auszuführen, Informationen offenzulegen, Informationen falsch darzustellen, einen Denial of Service Zustand herbeizuführen, Sicherheitsvorkehrungen zu umgehen, einen Cross-Site-Scripting-Angriff durchzuführen oder unbekannte Auswirkungen zu verursachen.

Official advisory ↗
BSI · German · WID-SEC-2023-1350Splunk Splunk Enterprise: Mehrere Schwachstellen in Komponenten von Drittanbietern

Ein Angreifer kann mehrere Schwachstellen in Splunk Splunk Enterprise in diversen Komponenten von Drittanbietern ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20210414Security Bulletin 14 Apr 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 14 Apr 2021, published on 14 April 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0428Multiples vulnérabilités dans les produits Splunk

d?id=CVE-2021-22922 Référence CVE CVE-2021-22923 https://www.cve.org/CVERecord?id=CVE-2021-22923 Référence CVE CVE-2021-22924 https://www.cve.org/CVERecord?id=CVE-2021-22924 Référence CVE CVE-2021-22925 https://www.cve.org/CVERecord?id=CVE-2021-22925 Référence CVE CVE-2021-22926 https://www.cve.org/CVERecord?id=CVE-2021-22926 Référence CVE CVE-2021-22945 https://www.cve.org/CVERecord?id=CVE-2021-22945 Référence CVE CVE-2021-22946 https://www.cve.org/CVERecord?id=CVE-2021-22946 Référence CVE CVE-2021-22947 https://www.cve.org/CVERecord?id=CVE-2021-22947 Référence CVE CVE-2021-23343 https://www.cve.org/CVERecord?id=CVE-2021-23343 Référence CVE CVE-2021-23368 https://www.cve.org/CVERecord?id=CVE-2021-23368 Référence CVE CVE-2021-23382 https://www.cve.org/CVERecord?id=CVE-2021-23382 Référence CVE CVE-2021-27292 https://www.cve.org/CVERecord?id=CVE-2021-27292 Référence CVE CVE-2021-29060 https://www.cve.org/CVERecord?id=CVE-2021-29060 Référence CVE CVE-2021-31566 https://www.cve.org/CVERecord?id=CVE-2021-31566 Référence CVE CVE-2021-33502 https://www.cve.org/CVERecord?id=CVE-2021-33502 Référence CVE CVE-2021-33503 https://www.cve.org/CVERecord?id=CVE-2021-33503 Référence CVE CVE-2021-33587 https://www.cve.org/CVERecord?id=CVE-2021-33587 Référence CVE CVE-2021-3520 https://www.cve.org/CVERecord?id=C

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0276Multiples vulnérabilités dans les produits IBM

ecord?id=CVE-2020-24025 Référence CVE CVE-2020-5259 https://www.cve.org/CVERecord?id=CVE-2020-5259 Référence CVE CVE-2020-7764 https://www.cve.org/CVERecord?id=CVE-2020-7764 Référence CVE CVE-2021-21290 https://www.cve.org/CVERecord?id=CVE-2021-21290 Référence CVE CVE-2021-21295 https://www.cve.org/CVERecord?id=CVE-2021-21295 Référence CVE CVE-2021-21409 https://www.cve.org/CVERecord?id=CVE-2021-21409 Référence CVE CVE-2021-23343 https://www.cve.org/CVERecord?id=CVE-2021-23343 Référence CVE CVE-2021-23362 https://www.cve.org/CVERecord?id=CVE-2021-23362 Référence CVE CVE-2021-23364 https://www.cve.org/CVERecord?id=CVE-2021-23364 Référence CVE CVE-2021-23368 https://www.cve.org/CVERecord?id=CVE-2021-23368 Référence CVE CVE-2021-23382 https://www.cve.org/CVERecord?id=CVE-2021-23382 Référence CVE CVE-2021-23450 https://www.cve.org/CVERecord?id=CVE-2021-23450 Référence CVE CVE-2021-25220 https://www.cve.org/CVERecord?id=CVE-2021-25220 Référence CVE CVE-2021-26401 https://www.cve.org/CVERecord?id=CVE-2021-26401 Référence CVE CVE-2021-29060 https://www.cve.org/CVERecord?id=CVE-2021-29060 Référence CVE CVE-2021-32803 https://www.cve.org/CVERecord?id=CVE-2021-32803 Référence CVE CVE-2021-32804 https://www.cve.org/CVERecord?id=CVE-2021-32804 Référence CVE CVE-2021-3677 https://www.cve.org/CVERecord?id=C

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-943Multiples vulnérabilités dans les produits IBM

d?id=CVE-2021-21347 Référence CVE CVE-2021-21348 https://www.cve.org/CVERecord?id=CVE-2021-21348 Référence CVE CVE-2021-21349 https://www.cve.org/CVERecord?id=CVE-2021-21349 Référence CVE CVE-2021-21350 https://www.cve.org/CVERecord?id=CVE-2021-21350 Référence CVE CVE-2021-21351 https://www.cve.org/CVERecord?id=CVE-2021-21351 Référence CVE CVE-2021-22930 https://www.cve.org/CVERecord?id=CVE-2021-22930 Référence CVE CVE-2021-22931 https://www.cve.org/CVERecord?id=CVE-2021-22931 Référence CVE CVE-2021-22939 https://www.cve.org/CVERecord?id=CVE-2021-22939 Référence CVE CVE-2021-22940 https://www.cve.org/CVERecord?id=CVE-2021-22940 Référence CVE CVE-2021-23368 https://www.cve.org/CVERecord?id=CVE-2021-23368 Référence CVE CVE-2021-29060 https://www.cve.org/CVERecord?id=CVE-2021-29060 Référence CVE CVE-2021-29505 https://www.cve.org/CVERecord?id=CVE-2021-29505 Référence CVE CVE-2021-29923 https://www.cve.org/CVERecord?id=CVE-2021-29923 Référence CVE CVE-2021-32027 https://www.cve.org/CVERecord?id=CVE-2021-32027 Référence CVE CVE-2021-32028 https://www.cve.org/CVERecord?id=CVE-2021-32028 Référence CVE CVE-2021-32029 https://www.cve.org/CVERecord?id=CVE-2021-32029 Référence CVE CVE-2021-33195 https://www.cve.org/CVERecord?id=CVE-2021-33195 Référence CVE CVE-2021-33197 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-005407postcss における脆弱性

postcss には、不特定の脆弱性が存在します。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
postcss: 7.0.0 < unspecified, unspecified < 8.2.10
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 12 Apr 2021 · Last source change 16 Sept 2024, 17:27 UTC · CWE not yet assigned

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-1108
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD modified after enrichment

Missing structured fields: CWE classification, affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-1108↗Public exploit reference↗Public exploit reference↗Patch or update reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-23368 · cve.blacktree.nl