Read the docs
TI-2023-12263 Aliases CVE-2023-27539GHSA-c6qg-cjj8-47qp

There is a denial of service vulnerability in the header parsing component of Rack.

Priority LOW 26Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · None
Fix status
Partial Red Hat: 13 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA, GitHub and Red Hat.

Summary

There is a denial of service vulnerability in the header parsing component of Rack.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01058 64th percentileScored 2026-11-07
Fix Partial Rack (Rails): 2.2.6.4, 3.0.6.1rack (RubyGems): 2.2.6.4, 3.0.6.1Red Hat: 8 advisoriesRed Hat: 13 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
RailsRack2.2.6.4 to before 2.2.6.4; 3.0.6.1 to before 3.0.6.12.2.6.4, 3.0.6.1Patch availableCNA
—rack (RubyGems)2.0.0 to before 2.2.6.42.2.6.4Patch availableGHSA-c6qg-cjj8-47qp
—rack (RubyGems)3.0.0 to before 3.0.6.13.0.6.1Patch availableGHSA-c6qg-cjj8-47qp
  • Rack VendorRails Affected 2.2.6.4 to before 2.2.6.4; 3.0.6.1 to before 3.0.6.1 Fixed in 2.2.6.4, 3.0.6.1 Patch available CNA
  • rack (RubyGems) Vendor— Affected 2.0.0 to before 2.2.6.4 Fixed in 2.2.6.4 Patch available GHSA-c6qg-cjj8-47qp
  • rack (RubyGems) Vendor— Affected 3.0.0 to before 3.0.6.1 Fixed in 3.0.6.1 Patch available GHSA-c6qg-cjj8-47qp

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*2.0.0 to before 2.2.6.4; 3.0.0 to before 3.0.6.1Vulnerablerack
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
  • cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:* Versions 2.0.0 to before 2.2.6.4; 3.0.0 to before 3.0.6.1 Vulnerable ·rack
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Rack (Rails) Fixed in 2.2.6.4, 3.0.6.1
  • Fix · GHSA-c6qg-cjj8-47qp rack (RubyGems) Fixed in 2.2.6.4 Advisory →
  • Fix · GHSA-c6qg-cjj8-47qp rack (RubyGems) Fixed in 3.0.6.1 Advisory →

Red Hat 8 advisories

  • RHSA-2023:6818 Released 2023-11-08 · Red Hat rating Important
    Satellite 6.14 security and bug fix update
    • Red Hat Satellite 6.14 for RHEL 8 foreman-3.7.0.9-1.el8sat, foreman-cli-3.7.0.9-1.el8sat, foreman-debug-3.7.0.9-1.el8sat +33
  • RHSA-2023:3495 Released 2023-06-12 · Red Hat rating Moderate
    Logging Subsystem 5.7.2 - Red Hat OpenShift security update
    • RHOL 5.7 for RHEL 8 openshift-logging/cluster-logging-rhel8-operator, openshift-logging/eventrouter-rhel8, openshift-logging/fluentd-rhel8
  • RHSA-2023:3403 Released 2023-05-31 · Red Hat rating Moderate
    pcs security and bug fix update
    • Red Hat Enterprise Linux High Availability EUS (v.8.6) pcs-0.10.12-6.el8_6.4, pcs-snmp-0.10.12-6.el8_6.4
    • Red Hat Enterprise Linux Resilient Storage EUS (v.8.6) pcs-0.10.12-6.el8_6.4, pcs-snmp-0.10.12-6.el8_6.4
Show 5 more Red Hat advisories
  • RHSA-2023:3082 Released 2023-05-16 · Red Hat rating Moderate
    pcs security and bug fix update
    • Red Hat Enterprise Linux HighAvailability (v. 8) pcs-0.10.15-4.el8_8.1, pcs-snmp-0.10.15-4.el8_8.1
    • Red Hat Enterprise Linux ResilientStorage (v. 8) pcs-0.10.15-4.el8_8.1, pcs-snmp-0.10.15-4.el8_8.1
  • RHSA-2023:2652 Released 2023-05-09 · Red Hat rating Important
    pcs security and bug fix update
    • Red Hat Enterprise Linux HighAvailability (v. 9) pcs-0.11.4-7.el9_2, pcs-snmp-0.11.4-7.el9_2
    • Red Hat Enterprise Linux ResilientStorage (v. 9) pcs-0.11.4-7.el9_2, pcs-snmp-0.11.4-7.el9_2
  • RHSA-2023:1953 Released 2023-04-26 · Red Hat rating Moderate
    Logging Subsystem 5.6.5 - Red Hat OpenShift security update
    • RHOL 5.6 for RHEL 8 openshift-logging/fluentd-rhel8
  • RHSA-2023:1981 Released 2023-04-25 · Red Hat rating Moderate
    pcs security and bug fix update
    • Red Hat Enterprise Linux High Availability EUS (v.9.0) pcs-0.11.1-10.el9_0.4, pcs-snmp-0.11.1-10.el9_0.4
    • Red Hat Enterprise Linux Resilient Storage EUS (v.9.0) pcs-0.11.1-10.el9_0.4, pcs-snmp-0.11.1-10.el9_0.4
  • RHSA-2023:1961 Released 2023-04-25 · Red Hat rating Moderate
    pcs security and bug fix update
    • Red Hat Enterprise Linux HighAvailability EUS (v.8.4) pcs-0.10.8-1.el8_4.4, pcs-snmp-0.10.8-1.el8_4.4
    • Red Hat Enterprise Linux ResilientStorage EUS (v.8.4) pcs-0.10.8-1.el8_4.4, pcs-snmp-0.10.8-1.el8_4.4

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat 3scale API Management Platform 2AffectedNo fix yet
Red Hat Storage 3AffectedNo fix planned: Will not fix
RHOL 5.6 for RHEL 8Fixed RHSA-2023:1953
RHOL 5.7 for RHEL 8Fixed RHSA-2023:3495
Red Hat Enterprise Linux High Availability EUS (v.8.6)Fixed RHSA-2023:3403
Red Hat Enterprise Linux High Availability EUS (v.9.0)Fixed RHSA-2023:1981
Red Hat Enterprise Linux HighAvailability (v. 8)Fixed RHSA-2023:3082
Red Hat Enterprise Linux HighAvailability (v. 9)Fixed RHSA-2023:2652
Red Hat Enterprise Linux HighAvailability EUS (v.8.4)Fixed RHSA-2023:1961
Red Hat Enterprise Linux Resilient Storage EUS (v.8.6)Fixed RHSA-2023:3403
Red Hat Enterprise Linux Resilient Storage EUS (v.9.0)Fixed RHSA-2023:1981
Red Hat Enterprise Linux ResilientStorage (v. 8)Fixed RHSA-2023:3082
Red Hat Enterprise Linux ResilientStorage (v. 9)Fixed RHSA-2023:2652
Red Hat Enterprise Linux ResilientStorage EUS (v.8.4)Fixed RHSA-2023:1961
Red Hat Satellite 6.14 for RHEL 8Fixed RHSA-2023:6818
Not affected: 4 products
  • RHOL 5.6 for RHEL 8
  • RHOL 5.7 for RHEL 8
  • Red Hat Enterprise Linux 7
  • Red Hat Satellite 6.14 for RHEL 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-27539
  2. 2026-10-03 Alias added: GHSA-c6qg-cjj8-47qp

References

Patch 3

Advisory 5

Other 3

  • TI-2014-00124 Directory traversal vulnerability in actionpack/lib/abstract_controller/base.rb in the… KEVCVSS 3.1HIGH 7.5
  • TI-2019-03828 Path traversal in Rails https://github.com/rails/rails KEVCVSS 3.1HIGH 7.5
  • TI-2016-00672 Directory traversal vulnerability in Action View in Ruby on Rails before 3.2.22.1, 4.0.x… KEVCVSS 3.1HIGH 7.5
  • TI-2019-03830 Command injection in Rails https://github.com/rails/rails CVSS 3.1CRITICAL 9.8
  • TI-2026-47043 Action Pack: Possible arbitrary file read and remote code execution in Active Storage variant processing CVSS 4.0CRITICAL 9.5
  • TI-2025-18040 Command injection in Rails activestorage CVSS 4.0CRITICAL 9.2
See all 163 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences