Bug 2364966 (CVE-2025-46727)

Summary:	CVE-2025-46727 rubygem-rack: Unbounded-Parameter DoS in Rack::QueryParser
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	akostadi, amasferr, anthomas, cbartlet, dmayorov, ehelms, ggainey, jcantril, jlledo, juwatts, mhulan, mmakovy, nmoumoul, osousa, pcreech, periklis, rchan, rojacob, smallamp, tjochec
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in Rack::QueryParser. This vulnerability allows denial of service via oversized HTTP requests containing many parameters, resulting in memory exhaustion that consumes all available memory or CPU resource pinning, which keeps the CPU constantly busy.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2364996, 2364997, 2364999, 2365000, 2364998
Bug Blocks:

Description OSIDB Bzimport 2025-05-08 00:01:08 UTC

Rack is a modular Ruby web server interface. Prior to versions 2.2.14, 3.0.16, and 3.1.14, `Rack::QueryParser` parses query strings and `application/x-www-form-urlencoded` bodies into Ruby data structures without imposing any limit on the number of parameters, allowing attackers to send requests with extremely large numbers of parameters. The vulnerability arises because `Rack::QueryParser` iterates over each `&`-separated key-value pair and adds it to a Hash without enforcing an upper bound on the total number of parameters. This allows an attacker to send a single request containing hundreds of thousands (or more) of parameters, which consumes excessive memory and CPU during parsing. An attacker can trigger denial of service by sending specifically crafted HTTP requests, which can cause memory exhaustion or pin CPU resources, stalling or crashing the Rack server. This results in full service disruption until the affected worker is restarted. Versions 2.2.14, 3.0.16, and 3.1.14 fix the issue. Some other mitigations are available. One may use middleware to enforce a maximum query string size or parameter count, or employ a reverse proxy (such as Nginx) to limit request sizes and reject oversized query strings or bodies. Limiting request body sizes and query string lengths at the web server or CDN level is an effective mitigation.

Comment 3 errata-xmlrpc 2025-05-14 14:12:12 UTC

This issue has been addressed in the following products:

  Red Hat Satellite 6.17 for RHEL 9

Via RHSA-2025:7604 https://access.redhat.com/errata/RHSA-2025:7604

Comment 4 errata-xmlrpc 2025-05-14 14:12:29 UTC

This issue has been addressed in the following products:

  Red Hat Satellite 6.16 for RHEL 8
  Red Hat Satellite 6.16 for RHEL 9

Via RHSA-2025:7605 https://access.redhat.com/errata/RHSA-2025:7605

Comment 5 errata-xmlrpc 2025-05-28 10:41:13 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2025:8254 https://access.redhat.com/errata/RHSA-2025:8254

Comment 6 errata-xmlrpc 2025-05-28 11:41:44 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:8256 https://access.redhat.com/errata/RHSA-2025:8256

Comment 7 errata-xmlrpc 2025-05-28 23:35:43 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Extended Update Support

Via RHSA-2025:8279 https://access.redhat.com/errata/RHSA-2025:8279

Comment 8 errata-xmlrpc 2025-05-29 06:26:42 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.6 Telecommunications Update Service

Via RHSA-2025:8290 https://access.redhat.com/errata/RHSA-2025:8290

Comment 9 errata-xmlrpc 2025-05-29 06:26:48 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2025:8291 https://access.redhat.com/errata/RHSA-2025:8291

Comment 10 errata-xmlrpc 2025-05-29 06:26:55 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Extended Update Support

Via RHSA-2025:8289 https://access.redhat.com/errata/RHSA-2025:8289

Comment 11 errata-xmlrpc 2025-05-29 06:27:05 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2025:8288 https://access.redhat.com/errata/RHSA-2025:8288

Comment 12 errata-xmlrpc 2025-05-29 15:47:53 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2025:8319 https://access.redhat.com/errata/RHSA-2025:8319

Comment 13 errata-xmlrpc 2025-05-29 16:07:30 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2025:8322 https://access.redhat.com/errata/RHSA-2025:8322

Comment 14 errata-xmlrpc 2025-05-29 16:40:33 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Telecommunications Update Service
  Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions

Via RHSA-2025:8323 https://access.redhat.com/errata/RHSA-2025:8323

Comment 15 errata-xmlrpc 2025-06-26 15:56:33 UTC

This issue has been addressed in the following products:

  Red Hat Satellite 6.15 for RHEL 8

Via RHSA-2025:9838 https://access.redhat.com/errata/RHSA-2025:9838