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TI-2025-38268 Aliases CVE-2025-61919GHSA-6xw4-3v39-52mm

Rack is vulnerable to a memory-exhaustion DoS through unbounded URL-encoded body parsing

Priority LOW 34CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 23 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

Rack is a modular Ruby web server interface. Prior to versions 2.2.20, 3.1.18, and 3.2.3, `Rack::Request#POST` reads the entire request body into memory for `Content-Type: application/x-www-form-urlencoded`, calling `rack.input.read(nil)` without enforcing a length or cap. Large request bodies can therefore be buffered completely into process memory before parsing, leading to denial of service (DoS) through memory exhaustion. Users should upgrade to Rack version 2.2.20, 3.1.18, or 3.2.3, anu of which enforces form parameter limits using `query_parser.bytesize_limit`, preventing unbounded reads of `application/x-www-form-urlencoded` bodies. Additionally, enforce strict maximum body size at the proxy or web server layer (e.g., Nginx `client_max_body_size`, Apache `LimitRequestBody`).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00648 51st percentileScored 2026-11-07
Fix Partial rack (rack): 2.2.20, 3.1.18, 3.2.3rack (RubyGems): 2.2.20, 3.1.18, 3.2.3Red Hat: 15 advisoriesRed Hat: 23 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
rackrackbefore 2.2.20; 3.0 to before 3.1.18; 3.2 to before 3.2.32.2.20, 3.1.18, 3.2.3Patch availableCNA
—rack (RubyGems)before 2.2.202.2.20Patch availableGHSA-6xw4-3v39-52mm
—rack (RubyGems)3.0 to before 3.1.183.1.18Patch availableGHSA-6xw4-3v39-52mm
—rack (RubyGems)3.2 to before 3.2.33.2.3Patch availableGHSA-6xw4-3v39-52mm
  • rack Vendorrack Affected before 2.2.20; 3.0 to before 3.1.18; 3.2 to before 3.2.3 Fixed in 2.2.20, 3.1.18, 3.2.3 Patch available CNA
  • rack (RubyGems) Vendor— Affected before 2.2.20 Fixed in 2.2.20 Patch available GHSA-6xw4-3v39-52mm
  • rack (RubyGems) Vendor— Affected 3.0 to before 3.1.18 Fixed in 3.1.18 Patch available GHSA-6xw4-3v39-52mm
  • rack (RubyGems) Vendor— Affected 3.2 to before 3.2.3 Fixed in 3.2.3 Patch available GHSA-6xw4-3v39-52mm

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*before 2.2.20; 3.0.0 to before 3.1.18; 3.2.0 to before 3.2.3Vulnerablerack
  • cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:* Versions before 2.2.20; 3.0.0 to before 3.1.18; 3.2.0 to before 3.2.3 Vulnerable ·rack

Remediation

  • Fix · CNA rack (rack) Fixed in 2.2.20, 3.1.18, 3.2.3
  • Fix · GHSA-6xw4-3v39-52mm rack (RubyGems) Fixed in 2.2.20 Advisory →
  • Fix · GHSA-6xw4-3v39-52mm rack (RubyGems) Fixed in 3.1.18 Advisory →
  • Fix · GHSA-6xw4-3v39-52mm rack (RubyGems) Fixed in 3.2.3 Advisory →

Red Hat 15 advisories

  • RHSA-2025:21696 Released 2025-11-18 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux Server HighAvailability (v. 7 ELS) pcs-0.9.169-3.el7_9.5, pcs-snmp-0.9.169-3.el7_9.5
    • Red Hat Enterprise Linux Server ResilientStorage (v. 7 ELS) pcs-0.9.169-3.el7_9.5, pcs-snmp-0.9.169-3.el7_9.5
  • RHSA-2025:21036 Released 2025-11-11 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability (v. 10) cockpit-ha-cluster-0.12.1-1.el10_1.1, pcs-0.12.1-1.el10_1.1, pcs-snmp-0.12.1-1.el10_1.1
  • RHSA-2025:20962 Released 2025-11-11 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability (v. 9) pcs-0.11.10-1.el9_7.1, pcs-snmp-0.11.10-1.el9_7.1
    • Red Hat Enterprise Linux Resilient Storage (v. 9) pcs-0.11.10-1.el9_7.1, pcs-snmp-0.11.10-1.el9_7.1
Show 12 more Red Hat advisories
  • RHSA-2025:19948 Released 2025-11-10 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability AUS (v.8.4) pcs-0.10.8-1.el8_4.8, pcs-snmp-0.10.8-1.el8_4.8
    • Red Hat Enterprise Linux HighAvailability EUS EXTENSION (v.8.4) pcs-0.10.8-1.el8_4.8, pcs-snmp-0.10.8-1.el8_4.8
  • RHSA-2025:19856 Released 2025-11-06 · Red Hat rating Important
    Satellite 6.15.5.6 Async Update
    • Red Hat Satellite 6.15 for RHEL 8 foreman-3.9.1.13-1.el8sat, foreman-cli-3.9.1.13-1.el8sat, foreman-debug-3.9.1.13-1.el8sat +13
  • RHSA-2025:19855 Released 2025-11-06 · Red Hat rating Important
    Satellite 6.16.5.5 Async Update
    • Red Hat Satellite 6.16 for RHEL 8 foreman-3.12.0.11-1.el8sat, foreman-cli-3.12.0.11-1.el8sat, foreman-debug-3.12.0.11-1.el8sat +13
    • Red Hat Satellite 6.16 for RHEL 9 foreman-3.12.0.11-1.el9sat, foreman-cli-3.12.0.11-1.el9sat, foreman-debug-3.12.0.11-1.el9sat +13
  • RHSA-2025:19832 Released 2025-11-05 · Red Hat rating Important
    Satellite 6.17.6 Async Update
    • Red Hat Satellite 6.17 for RHEL 9 foreman-3.14.0.10-1.el9sat, foreman-cli-3.14.0.10-1.el9sat, foreman-debug-3.14.0.10-1.el9sat +13
  • RHSA-2025:19800 Released 2025-11-05 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability E4S (v.9.0) pcs-0.11.1-10.el9_0.9, pcs-snmp-0.11.1-10.el9_0.9
    • Red Hat Enterprise Linux ResilientStorage E4S (v.9.0) pcs-0.11.1-10.el9_0.9, pcs-snmp-0.11.1-10.el9_0.9
  • RHSA-2025:19736 Released 2025-11-04 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability EUS (v.9.4) pcs-0.11.7-2.el9_4.5, pcs-snmp-0.11.7-2.el9_4.5
    • Red Hat Enterprise Linux Resilient Storage EUS (v.9.4) pcs-0.11.7-2.el9_4.5, pcs-snmp-0.11.7-2.el9_4.5
  • RHSA-2025:19734 Released 2025-11-04 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability E4S (v.8.6) pcs-0.10.12-6.el8_6.10, pcs-snmp-0.10.12-6.el8_6.10
    • Red Hat Enterprise Linux High Availability TUS (v.8.6) pcs-0.10.12-6.el8_6.10, pcs-snmp-0.10.12-6.el8_6.10
  • RHSA-2025:19733 Released 2025-11-04 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability E4S (v.9.2) pcs-0.11.4-7.el9_2.6, pcs-snmp-0.11.4-7.el9_2.6
    • Red Hat Enterprise Linux Resilient Storage E4S (v.9.2) pcs-0.11.4-7.el9_2.6, pcs-snmp-0.11.4-7.el9_2.6
  • RHSA-2025:19719 Released 2025-11-04 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux HighAvailability (v. 8) pcs-0.10.18-2.el8_10.7, pcs-snmp-0.10.18-2.el8_10.7
    • Red Hat Enterprise Linux ResilientStorage (v. 8) pcs-0.10.18-2.el8_10.7, pcs-snmp-0.10.18-2.el8_10.7
  • RHSA-2025:19647 Released 2025-11-04 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability E4S (v.8.8) pcs-0.10.15-4.el8_8.9, pcs-snmp-0.10.15-4.el8_8.9
    • Red Hat Enterprise Linux High Availability TUS (v.8.8) pcs-0.10.15-4.el8_8.9, pcs-snmp-0.10.15-4.el8_8.9
  • RHSA-2025:19512 Released 2025-11-03 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability (v. 9) pcs-0.11.9-2.el9_6.2, pcs-snmp-0.11.9-2.el9_6.2
    • Red Hat Enterprise Linux Resilient Storage (v. 9) pcs-0.11.9-2.el9_6.2, pcs-snmp-0.11.9-2.el9_6.2
  • RHSA-2025:19513 Released 2025-11-03 · Red Hat rating Important
    pcs security update
    • Red Hat Enterprise Linux High Availability (v. 10) cockpit-ha-cluster-0.12.0-3.el10_0.3, pcs-0.12.0-3.el10_0.3, pcs-snmp-0.12.0-3.el10_0.3

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat 3scale API Management Platform 2AffectedNo fix planned: Will not fix
Red Hat Satellite 6AffectedNo fix yet
Red Hat Enterprise Linux High Availability (v. 10)Fixed RHSA-2025:19513, RHSA-2025:21036
Red Hat Enterprise Linux High Availability (v. 9)Fixed RHSA-2025:19512, RHSA-2025:20962
Red Hat Enterprise Linux High Availability AUS (v.8.4)Fixed RHSA-2025:19948
Red Hat Enterprise Linux High Availability E4S (v.8.6)Fixed RHSA-2025:19734
Red Hat Enterprise Linux High Availability E4S (v.8.8)Fixed RHSA-2025:19647
Red Hat Enterprise Linux High Availability E4S (v.9.0)Fixed RHSA-2025:19800
Red Hat Enterprise Linux High Availability E4S (v.9.2)Fixed RHSA-2025:19733
Red Hat Enterprise Linux High Availability EUS (v.9.4)Fixed RHSA-2025:19736
Red Hat Enterprise Linux High Availability TUS (v.8.6)Fixed RHSA-2025:19734
Red Hat Enterprise Linux High Availability TUS (v.8.8)Fixed RHSA-2025:19647
Red Hat Enterprise Linux HighAvailability (v. 8)Fixed RHSA-2025:19719
Red Hat Enterprise Linux HighAvailability EUS EXTENSION (v.8.4)Fixed RHSA-2025:19948
Red Hat Enterprise Linux Resilient Storage (v. 9)Fixed RHSA-2025:19512, RHSA-2025:20962
Red Hat Enterprise Linux Resilient Storage E4S (v.9.2)Fixed RHSA-2025:19733
Red Hat Enterprise Linux Resilient Storage EUS (v.9.4)Fixed RHSA-2025:19736
Red Hat Enterprise Linux ResilientStorage (v. 8)Fixed RHSA-2025:19719
Red Hat Enterprise Linux ResilientStorage E4S (v.9.0)Fixed RHSA-2025:19800
Red Hat Enterprise Linux Server HighAvailability (v. 7 ELS)Fixed RHSA-2025:21696
Red Hat Enterprise Linux Server ResilientStorage (v. 7 ELS)Fixed RHSA-2025:21696
Red Hat Satellite 6.15 for RHEL 8Fixed RHSA-2025:19856
Red Hat Satellite 6.16 for RHEL 8Fixed RHSA-2025:19855
Red Hat Satellite 6.16 for RHEL 9Fixed RHSA-2025:19855
Red Hat Satellite 6.17 for RHEL 9Fixed RHSA-2025:19832
Not affected: 13 products
  • Logging Subsystem for Red Hat OpenShift
  • OpenShift Service Mesh 2
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenStack Platform 13 (Queens)
  • Red Hat Satellite 6.15 for RHEL 8
  • Red Hat Satellite 6.16 for RHEL 8
  • Red Hat Satellite 6.16 for RHEL 9
  • Red Hat Satellite 6.17 for RHEL 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-61919
  2. 2026-10-03 Alias added: GHSA-6xw4-3v39-52mm
  3. 2026-10-16 EPSS moved to the 50th–90th percentile

References

Patch 3

Advisory 2

Other 2

  • TI-2024-16580 Rack ReDos in content type parsing (2nd degree polynomial) CVSS 3.1HIGH 7.5
  • TI-2024-17236 Possible Denial of Service Vulnerability in Rack Header Parsing CVSS 3.1HIGH 7.5
  • TI-2024-17231 Possible DoS Vulnerability with Range Header in Rack CVSS 3.1HIGH 7.5
  • TI-2023-12254 Uncontrolled resource consumption in https://github.com/rack/rack CVSS 3.1HIGH 7.5
  • TI-2025-38165 Rack's multipart parser buffers unbounded per-part headers, enabling DoS (memory exhaustion) CVSS 3.1HIGH 7.5
  • TI-2025-38163 Rack's unbounded multipart preamble buffering enables DoS (memory exhaustion) CVSS 3.1HIGH 7.5
See all 36 →

Sources

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