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Full vulnerability report · 2024
CVE-2024-26146High confidence

Possible Denial of Service Vulnerability in Rack Header Parsing

rack · rack

Official source article: GitHub GHSA-54RR-7FVW-6X8F ↗. Check the applicable product and release in the original source.

5.3MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, 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 2.00% 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 rack rack 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: As exposure requiresRemediation target: Within 365 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.

5 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 · sourceruby-rackVendor fix publishedDebian records a fixed source-package version for this release.2.2.7-1.1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian bookwormbookworm · sourceruby-rackVendor fix publishedDebian records a fixed source-package version for this release.2.2.6.4-1+deb12u1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian forkyforky · sourceruby-rackVendor fix publishedDebian records a fixed source-package version for this release.2.2.7-1.1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian sidsid · sourceruby-rackVendor fix publishedDebian records a fixed source-package version for this release.2.2.7-1.1Debian Security Tracker ↗Source updated 6 Oct 2026
Ubuntu 24.04 LTSnoble · standard archiveruby-rackVendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.2.2.7-1ubuntu0.1Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Open-source package ranges8 source-attributed ranges

These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.

Ecosystem and packageAffected rangeFirst fixed versionEvidence
RubyGemsrackECOSYSTEM: introduced 3.0.0; fixed 3.0.9.13.0.9.1OSV record ↗aggregator derived · 10 Sep 2026
RubyGemsrackECOSYSTEM: introduced 2.2.0; fixed 2.2.8.12.2.8.1OSV record ↗aggregator derived · 10 Sep 2026
RubyGemsrackECOSYSTEM: introduced 2.1.0; fixed 2.1.4.42.1.4.4OSV record ↗aggregator derived · 10 Sep 2026
RubyGemsrackECOSYSTEM: introduced 0; fixed 2.0.9.42.0.9.4OSV record ↗aggregator derived · 10 Sep 2026
rubygemsrack>= 3.0.0, < 3.0.9.13.0.9.1GitHub advisory ↗upstream repository advisory · 18 Mar 2026
rubygemsrack>= 2.2.0, < 2.2.8.12.2.8.1GitHub advisory ↗upstream repository advisory · 18 Mar 2026
rubygemsrack>= 2.1.0, < 2.1.4.42.1.4.4GitHub advisory ↗upstream repository advisory · 18 Mar 2026
rubygemsrack< 2.0.9.42.0.9.4GitHub advisory ↗upstream repository advisory · 18 Mar 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-2024-26146 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityrubygem-rack: Possible Denial of Service Vulnerability in Rack Header Parsing
7 known affected

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

  • 3scale-amp-backend-container as a component of Red Hat 3scale API Management Platform 2
  • 3scale-amp-system-container as a component of Red Hat 3scale API Management Platform 2
  • 3scale-amp-zync-container as a component of Red Hat 3scale API Management Platform 2
  • pcs as a component of Red Hat Enterprise Linux 7
  • pcs-snmp as a component of Red Hat Enterprise Linux 7
  • pcs.src as a component of Red Hat Enterprise Linux 7
  • python-clufter as a component of Red Hat Enterprise Linux 7
Summary
A denial of service (DoS) vulnerability was found in rubygem-rack in how it parses Rack Header. Carefully crafted headers can cause header parsing in Rack to take longer than expected, resulting in a possible denial of service issue. Accept and Forwarded headers are impacted.
Remediation
Before applying this update, make sure all previously released errata relevant to your system have been applied. For detailed instructions how to apply this update, refer to: https://access.redhat.com/documentation/en-us/red_hat_satellite/6.15/html/updating_red_hat_satellite/index
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-2024-0516

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 actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

Rack is a modular Ruby web server interface. Carefully crafted headers can cause header parsing in Rack to take longer than expected resulting in a possible denial of service issue. Accept and Forwarded headers are impacted. Ruby 3.2 has mitigations for this problem, so Rack applications using Ruby 3.2 or newer are unaffected. This vulnerability is fixed in 2.0.9.4, 2.1.4.4, 2.2.8.1, and 3.0.9.1.

What

Rack is a modular Ruby web server interface. Carefully crafted headers can cause header parsing in Rack to take longer than expected resulting in a possible denial of service issue. Accept and Forwarded headers are impacted. Ruby 3.2 has mitigations for this problem, so Rack applications using Ruby 3.2 or newer are unaffected. This vulnerability is fixed in 2.0.9.4, 2.1.4.4, 2.2.8.1, and 3.0.9.1.

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

Rack is a modular Ruby web server interface. Carefully crafted headers can cause header parsing in Rack to take longer than expected resulting in a possible denial of service issue. Accept and Forwarded headers are impacted. Ruby 3.2 has mitigations for this problem, so Rack applications using Ruby 3.2 or newer are unaffected. This vulnerability is fixed in 2.0.9.4, 2.1.4.4, 2.2.8.1, and 3.0.9.1.

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: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 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-2024-0911Red Hat Enterprise Linux (pcs): Mehrere Schwachstellen ermöglichen Denial of Service

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux (pcs) ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20240306Security Bulletin 06 Mar 2024

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 06 Mar 2024, published on 6 March 2024. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-1129Multiples vulnérabilités dans les produits VMware

rd?id=CVE-2020-7792 Référence CVE CVE-2022-29526 https://www.cve.org/CVERecord?id=CVE-2022-29526 Référence CVE CVE-2023-45288 https://www.cve.org/CVERecord?id=CVE-2023-45288 Référence CVE CVE-2023-48795 https://www.cve.org/CVERecord?id=CVE-2023-48795 Référence CVE CVE-2024-12905 https://www.cve.org/CVERecord?id=CVE-2024-12905 Référence CVE CVE-2024-21538 https://www.cve.org/CVERecord?id=CVE-2024-21538 Référence CVE CVE-2024-25126 https://www.cve.org/CVERecord?id=CVE-2024-25126 Référence CVE CVE-2024-25621 https://www.cve.org/CVERecord?id=CVE-2024-25621 Référence CVE CVE-2024-26141 https://www.cve.org/CVERecord?id=CVE-2024-26141 Référence CVE CVE-2024-26146 https://www.cve.org/CVERecord?id=CVE-2024-26146 Référence CVE CVE-2024-3044 https://www.cve.org/CVERecord?id=CVE-2024-3044 Référence CVE CVE-2024-34155 https://www.cve.org/CVERecord?id=CVE-2024-34155 Référence CVE CVE-2024-34158 https://www.cve.org/CVERecord?id=CVE-2024-34158 Référence CVE CVE-2024-45336 https://www.cve.org/CVERecord?id=CVE-2024-45336 Référence CVE CVE-2024-45337 https://www.cve.org/CVERecord?id=CVE-2024-45337 Référence CVE CVE-2024-45341 https://www.cve.org/CVERecord?id=CVE-2024-45341 Référence CVE CVE-2025-0913 https://www.cve.org/CVERecord?id=CVE-2025-0913 Référence CVE CVE-2025-12194 https://www.cve.org/CVERecord?id=CVE-

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-0969Multiples vulnérabilités dans les produits VMware

ord?id=CVE-2024-24788 Référence CVE CVE-2024-24789 https://www.cve.org/CVERecord?id=CVE-2024-24789 Référence CVE CVE-2024-24790 https://www.cve.org/CVERecord?id=CVE-2024-24790 Référence CVE CVE-2024-24791 https://www.cve.org/CVERecord?id=CVE-2024-24791 Référence CVE CVE-2024-25062 https://www.cve.org/CVERecord?id=CVE-2024-25062 Référence CVE CVE-2024-2511 https://www.cve.org/CVERecord?id=CVE-2024-2511 Référence CVE CVE-2024-25126 https://www.cve.org/CVERecord?id=CVE-2024-25126 Référence CVE CVE-2024-25260 https://www.cve.org/CVERecord?id=CVE-2024-25260 Référence CVE CVE-2024-26141 https://www.cve.org/CVERecord?id=CVE-2024-26141 Référence CVE CVE-2024-26146 https://www.cve.org/CVERecord?id=CVE-2024-26146 Référence CVE CVE-2024-26256 https://www.cve.org/CVERecord?id=CVE-2024-26256 Référence CVE CVE-2024-26458 https://www.cve.org/CVERecord?id=CVE-2024-26458 Référence CVE CVE-2024-26461 https://www.cve.org/CVERecord?id=CVE-2024-26461 Référence CVE CVE-2024-26462 https://www.cve.org/CVERecord?id=CVE-2024-26462 Référence CVE CVE-2024-26700 https://www.cve.org/CVERecord?id=CVE-2024-26700 Référence CVE CVE-2024-26726 https://www.cve.org/CVERecord?id=CVE-2024-26726 Référence CVE CVE-2024-26775 https://www.cve.org/CVERecord?id=CVE-2024-26775 Référence CVE CVE-2024-26896 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0160Multiples vulnérabilités dans Ruby on Rails

De multiples vulnérabilités ont été découvertes dans Ruby on Rails. Elles permettent à un attaquant de provoquer un déni de service à distance, une atteinte à la confidentialité des données et une injection de code indirecte à distance (XSS).

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2024-019061Rack の Rack 等複数ベンダの製品における非効率的な正規表現の複雑さに関する脆弱性

Rack の Rack 等複数ベンダの製品には、非効率的な正規表現の複雑さに関する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
Before applying this update, make sure all previously released errata relevant to your system have been applied. For detailed instructions how to apply this update, refer to: https://access.redhat.com/documentation/en-us/red_hat_satellite/6.15/html/updating_red_hat_satellite/index
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 28 Feb 2024 · Last source change 13 Feb 2025, 17:41 UTC · CWE-1333 · Inefficient Regular Expression Complexity

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-2024-0516
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    >= 3.0.0, < 3.0.9.1; >= 2.2.0, < 2.2.8.1; >= 2.1.0, < 2.1.4.4; < 2.0.9.4 · 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.
    After
    >= 3.0.0, < 3.0.9.1; >= 2.2.0, < 2.2.8.1; >= 2.1.0, < 2.1.4.4; < 2.0.9.4 · Fixed: Before applying this update, make sure all previously released errata relevant to your system have been applied. For detailed instructions how to apply this update, refer to: https://access.redhat.com/documentation/en-us/red_hat_satellite/6.15/html/updating_red_hat_satellite/index
    Red Hat Product Security ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
Fixed release recorded from official guidance
ENISA EUVD · EUVD-2024-0516↗Red Hat Product Security security advisory↗CVE authority or vendor reference · GitHub GHSA-54RR-7FVW-6X8F↗Patch or update 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-2024-26146 · cve.blacktree.nl