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TI-2026-47752 Aliases CVE-2026-67591GHSA-xcxh-hgpq-crj6

Apache Qpid ProtonJ2: Incoming session flow control window can be exceeded

Priority LOW 30CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Deferred Red Hat: fix deferred

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-770.

Summary

An authenticated attacker could exceed the session flow control incoming window potentially leading to denial of service. This issue affects Apache Qpid ProtonJ2: through 1.1.0. Users are recommended to upgrade to version 1.2.0, which fixes the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00653 51st percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred

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
ApacheApache Qpid ProtonJ2up to 1.1.0—No fix listedCNA
  • Apache Qpid ProtonJ2 VendorApache Affected up to 1.1.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:qpid_protonj2:*:*:*:*:*:*:*:*before 1.2.0VulnerableApache
  • cpe:2.3:a:apache:qpid_protonj2:*:*:*:*:*:*:*:* Versions before 1.2.0 Vulnerable ·Apache

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat AMQ Broker 7AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-67591
  2. 2026-10-03 Alias added: GHSA-xcxh-hgpq-crj6
  3. 2026-10-14 EPSS moved to the 50th–90th percentile

References

Advisory 2

  • TI-2026-47753 Apache Qpid ProtonJ2: Unable to govern the maximum number of transfer frames per incoming delivery CVSS 3.1HIGH 7.5
  • TI-2026-47751 Apache Qpid ProtonJ2: Unbounded type nesting can lead to pre-authentication stackoverflow CVSS 3.1HIGH 7.5
  • TI-2026-47750 Apache Qpid ProtonJ2: Type size/count handling can lead to excessive allocation pre-authentication CVSS 3.1HIGH 7.5
  • TI-2026-47749 Apache Qpid ProtonJ2: Unbounded symbol value caching can lead to pre-authentication resource exhaustion CVSS 3.1HIGH 7.5

Sources

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