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TI-2019-12562 Aliases CVE-2019-16782GHSA-hrqr-hxpp-chr3

Possible Information Leak / Session Hijack Vulnerability in Rack

Priority LOW 34CWE-208Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 5 fixed, 4 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-208.

Summary

There's a possible information leak / session hijack vulnerability in Rack (RubyGem rack). This vulnerability is patched in versions 1.6.12 and 2.0.8. Attackers may be able to find and hijack sessions by using timing attacks targeting the session id. Session ids are usually stored and indexed in a database that uses some kind of scheme for speeding up lookups of that session id. By carefully measuring the amount of time it takes to look up a session, an attacker may be able to find a valid session id and hijack the session. The session id itself may be generated randomly, but the way the session is indexed by the backing store does not use a secure comparison.

Why it matters now

EPSS 0.03703 89th percentileScored 2026-11-07
Fix Partial rack (RubyGems): 1.6.12, 2.0.8Red Hat: 3 advisoriesRed Hat: 5 fixed, 4 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
rackrackbefore 1.6.12 or 2.0.8—No fix listedCNA
—rack (RubyGems)before 1.6.121.6.12Patch availableGHSA-hrqr-hxpp-chr3
—rack (RubyGems)2.0.0 to before 2.0.82.0.8Patch availableGHSA-hrqr-hxpp-chr3
  • rack Vendorrack Affected before 1.6.12 or 2.0.8 Fixed in — No fix listed CNA
  • rack (RubyGems) Vendor— Affected before 1.6.12 Fixed in 1.6.12 Patch available GHSA-hrqr-hxpp-chr3
  • rack (RubyGems) Vendor— Affected 2.0.0 to before 2.0.8 Fixed in 2.0.8 Patch available GHSA-hrqr-hxpp-chr3

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*before 1.6.12; 2.0.0 to before 2.0.8Vulnerablerack
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*31VulnerableFedoraproject
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*15.1VulnerableopenSUSE
  • cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:* Versions before 1.6.12; 2.0.0 to before 2.0.8 Vulnerable ·rack
  • cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
  • cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* Versions 15.1 Vulnerable ·openSUSE

Remediation

  • Fix · GHSA-hrqr-hxpp-chr3 rack (RubyGems) Fixed in 1.6.12 Advisory →
  • Fix · GHSA-hrqr-hxpp-chr3 rack (RubyGems) Fixed in 2.0.8 Advisory →

Red Hat 3 advisories

  • RHSA-2021:1313 Released 2021-04-21 · Red Hat rating Moderate
    Satellite 6.9 Release
    • Red Hat Satellite 6.9 ansible-collection-redhat-satellite-2.0.1-1.el7sat, ansible-runner-1.4.6-1.el7ar, ansiblerole-foreman_scap_client-0.1.0-1.el7sat +47
    • Red Hat Satellite Capsule 6.9 ansible-collection-redhat-satellite-2.0.1-1.el7sat, ansible-runner-1.4.6-1.el7ar, ansiblerole-foreman_scap_client-0.1.0-1.el7sat +47
  • RHSA-2020:4366 Released 2020-10-27 · Red Hat rating Important
    Satellite 6.8 release
    • Red Hat Satellite 6.8 ansible-collection-redhat-satellite-1.3.0-1.el7sat, ansible-runner-1.4.6-1.el7ar, ansiblerole-foreman_scap_client-0.0.5-1.el7sat +47
    • Red Hat Satellite Capsule 6.8 ansible-collection-redhat-satellite-1.3.0-1.el7sat, ansible-runner-1.4.6-1.el7ar, ansiblerole-foreman_scap_client-0.0.5-1.el7sat +47
  • RHSA-2020:2480 Released 2020-06-10 · Red Hat rating Moderate
    CloudForms 5.0.6 security, bug fix and enhancement update
    • CloudForms Management Engine 5.11 ansible-runner-1.4.6-1.el8ar, cfme-5.11.6.0-1.el8cf, cfme-amazon-smartstate-5.11.6.0-1.el8cf +6

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat OpenStack Platform 10 (Newton) Operational ToolsAffectedNo fix planned: Out of support scope
Red Hat Satellite 6AffectedNo fix yet
Red Hat Software CollectionsAffectedNo fix planned: Will not fix
Red Hat Storage 3AffectedNo fix planned: Will not fix
CloudForms Management Engine 5.11Fixed RHSA-2020:2480
Red Hat Satellite 6.8Fixed RHSA-2020:4366
Red Hat Satellite 6.9Fixed RHSA-2021:1313
Red Hat Satellite Capsule 6.8Fixed RHSA-2020:4366
Red Hat Satellite Capsule 6.9Fixed RHSA-2021:1313
Not affected: 2 products
  • Red Hat OpenStack Platform 13 (Queens) Operational Tools
  • Red Hat Satellite 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-16782
  2. 2026-10-03 Alias added: GHSA-hrqr-hxpp-chr3

References

Patch 2

Advisory 8

Other 4

  • 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