Bug 2398167 (CVE-2025-59830)

Summary: CVE-2025-59830 rubygem-rack: Rack QueryParser has an unsafe default allowing params_limit bypass via semicolon-separated parameters
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akostadi, amasferr, anthomas, cbartlet, crizzo, dmayorov, eglynn, ehelms, ggainey, jcantril, jjoyce, jlledo, jschluet, juwatts, jvasik, kaycoth, lhh, lsvaty, mburns, mgarciac, mhulan, mkudlej, mmakovy, nmoumoul, osousa, pantinor, pcreech, pgrist, rblanco, rchan, rojacob, smallamp, tjochec, tmalecek, tsedmik, vmugicag
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
An unsafe default behavior in Rack::QueryParser allows bypass of the params_limit parameter count restriction when query string parameters are delimited by semicolons (;) rather than ampersands (&). The parser counts only & when enforcing the limit, while still splitting on both & and ;. As a result, an attacker can supply a crafted HTTP query using ; delimiters to exceed the intended parameter count, potentially causing performance degradation or exhaustion of resources (denial of service).
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: 2402984, 2402985, 2402986, 2402982, 2402983, 2402987, 2402988    
Bug Blocks:    

Description OSIDB Bzimport 2025-09-25 15:02:05 UTC
Rack is a modular Ruby web server interface. Prior to version 2.2.18, Rack::QueryParser enforces its params_limit only for parameters separated by &, while still splitting on both & and ;. As a result, attackers could use ; separators to bypass the parameter count limit and submit more parameters than intended. Applications or middleware that directly invoke Rack::QueryParser with its default configuration (no explicit delimiter) could be exposed to increased CPU and memory consumption. This can be abused as a limited denial-of-service vector. This issue has been patched in version 2.2.18.

Comment 6 errata-xmlrpc 2025-11-03 20:11:08 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2025:19513 https://access.redhat.com/errata/RHSA-2025:19513

Comment 7 errata-xmlrpc 2025-11-03 20:18:29 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:19512 https://access.redhat.com/errata/RHSA-2025:19512

Comment 8 errata-xmlrpc 2025-11-04 11:16:18 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2025:19647 https://access.redhat.com/errata/RHSA-2025:19647

Comment 9 errata-xmlrpc 2025-11-04 17:00:42 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2025:19719 https://access.redhat.com/errata/RHSA-2025:19719

Comment 10 errata-xmlrpc 2025-11-04 19:47:31 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2025:19733 https://access.redhat.com/errata/RHSA-2025:19733

Comment 11 errata-xmlrpc 2025-11-04 19:58:26 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-2025:19734 https://access.redhat.com/errata/RHSA-2025:19734

Comment 12 errata-xmlrpc 2025-11-04 23:33:48 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2025:19736 https://access.redhat.com/errata/RHSA-2025:19736

Comment 13 errata-xmlrpc 2025-11-05 13:07:45 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2025:19800 https://access.redhat.com/errata/RHSA-2025:19800

Comment 14 errata-xmlrpc 2025-11-05 23:45:42 UTC
This issue has been addressed in the following products:

  Red Hat Satellite 6.17 for RHEL 9

Via RHSA-2025:19832 https://access.redhat.com/errata/RHSA-2025:19832

Comment 15 errata-xmlrpc 2025-11-06 02:23:46 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-2025:19855 https://access.redhat.com/errata/RHSA-2025:19855

Comment 16 errata-xmlrpc 2025-11-06 02:25:01 UTC
This issue has been addressed in the following products:

  Red Hat Satellite 6.15 for RHEL 8

Via RHSA-2025:19856 https://access.redhat.com/errata/RHSA-2025:19856

Comment 17 errata-xmlrpc 2025-11-10 01:34:43 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 Extended Update Support Long-Life Add-On

Via RHSA-2025:19948 https://access.redhat.com/errata/RHSA-2025:19948

Comment 18 errata-xmlrpc 2025-11-11 15:01:21 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:20962 https://access.redhat.com/errata/RHSA-2025:20962

Comment 19 errata-xmlrpc 2025-11-11 19:49:01 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2025:21036 https://access.redhat.com/errata/RHSA-2025:21036