Free and open · new CVEs checked every 20 minutesStatusRSSOpen dataContact

CVE-2026-9336: IBM WebSphere Application Server 9.0, and 8.5 is vulnerable to a denial of service, caused by sending a specia

37
Routine
MEDIUM 6.5UPGRADE

CVE-2026-9336 is a medium-severity flaw (CVSS 6.5) affecting websphere application server. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

IBM WebSphere Application Server 9.0, and 8.5 is vulnerable to a denial of service, caused by sending a specially-crafted HTTP request to an administrative endpoint. A remote attacker could exploit this vulnerability to cause the server to exhaust filesystem space.

Why this priority

  • No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score6.5 (Medium)
Attack vectorAdjacent network
Attack complexityLow
Privileges neededNone
User interactionNone
EPSS exploit chance0.8% (top 45%)
CISA exploited listNo
WeaknessCWE-306
Published2026-09-10
Last modified2026-09-16
Publisher (CNA): IBM Corporation · Vendor: ibm

Share: LinkedIn · X · Reddit

Last updated 2026-09-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

ibm websphere application server UPGRADE
Affected: >= 8.5.0.0 and < 8.5.5.31 · >= 9.0.0.0 and < 9.0.5.29
Fixed in: 8.5.5.31, 9.0.5.29
Safe to downgrade to: a release before 8.5.0.0
1. Check installed version
apt-cache policy websphere-application-server || rpm -q websphere-application-server || websphere-application-server --version
2. UPGRADE to 8.5.5.31 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade websphere-application-server
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade websphere-application-server
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 8.5.0.0 (Debian / Ubuntu)
apt-cache madison websphere-application-server sudo apt install websphere-application-server=<VERSION_BEFORE_8.5.0.0> sudo apt-mark hold websphere-application-server
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list websphere-application-server sudo dnf downgrade websphere-application-server-<VERSION_BEFORE_8.5.0.0> sudo dnf versionlock add websphere-application-server
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
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.

Quick answers

How do I fix CVE-2026-9336?

websphere application server: upgrade to 8.5.5.31, 9.0.5.29. Exact commands for each OS are on this page.

Is CVE-2026-9336 being exploited?

CVE-2026-9336 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-9336 affect?

CVE-2026-9336 affects websphere application server. Severity is medium (CVSS 6.5). IBM WebSphere Application Server 9.0, and 8.5 is vulnerable to a denial of service, caused by sending a specially-crafted HTTP request to an administrative endpoint. A remote attacker could exploit this vulnerability to cause the server to

How urgent is CVE-2026-9336?

Priority 37/100. No elevated risk signals yet.

Software pages

IBM WebSphere vulnerabilities

Related CVEs

References

← Back to latest CVEs

Get the weekly exploited-CVE digest by emailThe CVEs being attacked this week and how to fix them. No spam, unsubscribe any time.