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Full vulnerability report · 2021
CVE-2021-33502High confidence

n/a — Inefficient Regular Expression Complexity

Unknown · Unknown

7.5HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:High, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 1.70% 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.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown Unknown 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, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

6 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-gotVendor fix publishedDebian records a fixed source-package version for this release.11.8.1+~cs53.13.17-3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcenode-gotVendor fix publishedDebian records a fixed source-package version for this release.11.8.1+~cs53.13.17-3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcenode-gotVendor fix publishedDebian records a fixed source-package version for this release.11.8.1+~cs53.13.17-3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcenode-gotVendor fix publishedDebian records a fixed source-package version for this release.11.8.1+~cs53.13.17-3Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivenode-gotUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivenode-yarnpkgUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 5 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2021-33502 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitynodejs-normalize-url: ReDoS for data URLs
5 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • rhacm2/mcm-topology-api-rhel8 as a component of Red Hat Advanced Cluster Management for Kubernetes 2
  • rhacm2/search-api-rhel8 as a component of Red Hat Advanced Cluster Management for Kubernetes 2
  • rhacm2/search-ui-rhel8 as a component of Red Hat Advanced Cluster Management for Kubernetes 2
  • nodejs-nodemon.src (nodejs:12) as a component of Red Hat Enterprise Linux 8
  • nodejs-nodemon (nodejs:12) as a component of Red Hat Enterprise Linux 8
Summary
A flaw was found in normalize-url. Node.js has a ReDoS (regular expression denial of service) issue because it has exponential performance for data.
Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
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-2021-1374

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

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

The normalize-url package before 4.5.1, 5.x before 5.3.1, and 6.x before 6.0.1 for Node.js has a ReDoS (regular expression denial of service) issue because it has exponential performance for data: URLs.

What

The normalize-url package before 4.5.1, 5.x before 5.3.1, and 6.x before 6.0.1 for Node.js has a ReDoS (regular expression denial of service) issue because it has exponential performance for data: URLs.

Why

The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

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 normalize-url package before 4.5.1, 5.x before 5.3.1, and 6.x before 6.0.1 for Node.js has a ReDoS (regular expression denial of service) issue because it has exponential performance for data: URLs.

Why

The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

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.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Inefficient Regular Expression Complexity → 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: a standard category for the underlying weakness.
CWE-1333 ↗

CWE-1333: Inefficient Regular Expression Complexity. The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

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:H

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.AHighAvailability impact: A successful attack can cause a major 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 serviceCWE-1333
A

Official authority intelligence

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

BSI · German · WID-SEC-2023-0856IBM QRadar SIEM: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

Official advisory ↗
BSI · German · WID-SEC-2023-0857IBM QRadar SIEM: Mehrere Schwachstellen

Ein lokaler Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um beliebigen Programmcode auszuführen, einen Denial of Service Zustand herbeizuführen, Dateien manipulieren oder Sicherheitsvorkehrungen zu umgehen.

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-20210526Security Bulletin 26 May 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 26 May 2021, published on 26 May 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-2021-22945 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=CVE-2021-3520 Référence CVE CVE-2021-36976 https://www.cve.org/CVERecord?id=CVE-2021-36976 Référence CVE CVE-2021-3803 https://www.cve.org/CVERecord?id=CVE-2021-3803 Référence CVE CVE-2021-43565 https://www.cve.org/CVERecord?id=CVE-2021-43565 Référence CVE CVE-2022-1705 https://www.cve.org/CVERecord?id=CVE-2022-1705 Référence CVE CVE-2022-1962 https://www.cve.org/CVERecord?id=CVE-202

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0076Multiples vulnérabilités dans les produits IBM

De multiples vulnérabilités ont été découvertes dans les produits IBM. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-928Multiples vulnérabilités dans les produits IBM

ord?id=CVE-2021-22569 Référence CVE CVE-2021-22959 https://www.cve.org/CVERecord?id=CVE-2021-22959 Référence CVE CVE-2021-22960 https://www.cve.org/CVERecord?id=CVE-2021-22960 Référence CVE CVE-2021-23337 https://www.cve.org/CVERecord?id=CVE-2021-23337 Référence CVE CVE-2021-23450 https://www.cve.org/CVERecord?id=CVE-2021-23450 Référence CVE CVE-2021-29425 https://www.cve.org/CVERecord?id=CVE-2021-29425 Référence CVE CVE-2021-3177 https://www.cve.org/CVERecord?id=CVE-2021-3177 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-2021-33502 https://www.cve.org/CVERecord?id=CVE-2021-33502 Référence CVE CVE-2021-34538 https://www.cve.org/CVERecord?id=CVE-2021-34538 Référence CVE CVE-2021-3711 https://www.cve.org/CVERecord?id=CVE-2021-3711 Référence CVE CVE-2021-3712 https://www.cve.org/CVERecord?id=CVE-2021-3712 Référence CVE CVE-2021-3733 https://www.cve.org/CVERecord?id=CVE-2021-3733 Référence CVE CVE-2021-3737 https://www.cve.org/CVERecord?id=CVE-2021-3737 Référence CVE CVE-2021-3765 https://www.cve.org/CVERecord?id=CVE-2021-3765 Référence CVE CVE-2021-37701 https://www.cve.org/CVERecord?id=CVE-2021-37701 Référence CVE CVE-2021-37712 https://www.cve.org/CVERecord?id=CVE-2021-3

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-924Multiples vulnérabilités dans IBM QRadar

cord?id=CVE-2020-7788 Référence CVE CVE-2020-8203 https://www.cve.org/CVERecord?id=CVE-2020-8203 Référence CVE CVE-2021-22959 https://www.cve.org/CVERecord?id=CVE-2021-22959 Référence CVE CVE-2021-22960 https://www.cve.org/CVERecord?id=CVE-2021-22960 Référence CVE CVE-2021-23337 https://www.cve.org/CVERecord?id=CVE-2021-23337 Référence CVE CVE-2021-23346 https://www.cve.org/CVERecord?id=CVE-2021-23346 Référence CVE CVE-2021-23566 https://www.cve.org/CVERecord?id=CVE-2021-23566 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-2021-33502 https://www.cve.org/CVERecord?id=CVE-2021-33502 Référence CVE CVE-2021-3765 https://www.cve.org/CVERecord?id=CVE-2021-3765 Référence CVE CVE-2021-37701 https://www.cve.org/CVERecord?id=CVE-2021-37701 Référence CVE CVE-2021-37712 https://www.cve.org/CVERecord?id=CVE-2021-37712 Référence CVE CVE-2021-37713 https://www.cve.org/CVERecord?id=CVE-2021-37713 Référence CVE CVE-2021-3807 https://www.cve.org/CVERecord?id=CVE-2021-3807 Référence CVE CVE-2021-3918 https://www.cve.org/CVERecord?id=CVE-2021-3918 Référence CVE CVE-2021-44906 https://www.cve.org/CVERecord?id=CVE-2021-44906 Référence CVE CVE-2021-44907 https://www.cve.org/CVERecord?id=CVE-20

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-510Multiples vulnérabilités dans IBM QRadar

d?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-2021-23343 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-2021-27290 https://www.cve.org/CVERecord?id=CVE-2021-27290 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-2021-33502 https://www.cve.org/CVERecord?id=CVE-2021-33502 Référence CVE CVE-2021-3672 https://www.cve.org/CVERecord?id=CVE-2021-3672 Référence CVE CVE-2021-37701 https://www.cve.org/CVERecord?id=CVE-2021-37701 Référence CVE CVE-2021-37712 https://www.cve.org/CVERecord?id=CVE-2021-37712 Référence CVE CVE-2021-37713 https://www.cve.org/CVERecord?id=CVE-2021-37713 Référence CVE CVE-2021-3807 https://www.cve.org/CVERecord?id=CVE-2021-3807 Référence CVE CVE-2021-3918 https://www.cve.org/CVERecord?id=CVE-2021-3918 Gestion détaillée du document le 01 juin 2022 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-494Multiples vulnérabilités dans les produits IBM

De multiples vulnérabilités ont été découvertes dans les produits IBM. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et un contournement de la politique de sécurité.

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

d?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=CVE-2021-33197 Référence CVE CVE-2021-33502 https://www.cve.org/CVERecord?id=CVE-2021-33502 Référence CVE CVE-2021-33909 https://www.cve.org/CVERecord?id=CVE-2021-33909 Référence CVE CVE-2021-34558 https://www.cve.org/CVERecord?id=CVE-2021-34558 Référence CVE CVE-2021-35065 https://www.cve.org/CVERecord?id=CVE-2021-35065 Référence CVE CVE-2021-35515 https://www.cve.org/CVERecord?id=CVE-2021-35515 Référence CVE CVE-2021-35516 https://www.cve.org/CVERecord?id=CVE-2021-35516 Référence CVE CVE-2021-35517 https://www.cve.org/CVERecord?id=CVE-2021-35517 Référence CVE CVE-2021-36090 https://www.cve.org/CVERecord?id=CVE-2021-36090 Référence CVE CVE-2021-36221 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-007290normalize-url パッケージにおける脆弱性

normalize-url パッケージには、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
Fixed
Action
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
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 24 May 2021 · Last source change 3 Aug 2024, 23:50 UTC · CWE-1333 · Inefficient Regular Expression Complexity

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
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-2021-1374
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

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

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    n/a · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    n/a · Fixed: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
    Red Hat Product Security ↗
  2. Remediation statusRemediation status changed from Awaiting fix to Patch available.
    Before
    Awaiting fix
    After
    Patch available
    Red Hat Product Security ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release recorded from official guidance
ENISA EUVD · EUVD-2021-1374↗Red Hat Product Security security advisory↗CVE authority or vendor 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-2021-33502 · cve.blacktree.nl