PatchTheCVECVE-2026-67591: An authenticated attacker could exceed the session flow control incoming window potentially leading to denial
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MEDIUM 6.5WATCHLISTUPGRADE
CVE-2026-67591 is a medium-severity flaw (CVSS 6.5) affecting qpid protonj2. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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 this priority
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.7% (top 49%) |
| CISA exploited list | No |
| Weakness | CWE-770 |
| Published | 2026-08-05 |
| Last modified | 2026-10-23 |
Publisher (CNA): Apache Software Foundation · Vendor: apache
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
apache qpid protonj2 UPGRADE
Affected: < 1.2.0
Fixed in: 1.2.0
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy qpid-protonj2 || rpm -q qpid-protonj2 || qpid-protonj2 --version
2. UPGRADE to 1.2.0 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade qpid-protonj2
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade qpid-protonj2
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
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