CVE-2009-1088: Hannon Hill Cascade Server 5.7 and other versions allows remote authenticated users to execute arbitrary progr

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HIGH 9.0DOWNGRADE

CVE-2009-1088 is a high-severity flaw (CVSS 9.0) affecting cascade. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Hannon Hill Cascade Server 5.7 and other versions allows remote authenticated users to execute arbitrary programs or Java code via a crafted XSLT stylesheet with "extension elements and extension functions" that trigger code execution by Xalan-Java, as demonstrated using xalan://java.lang.Runtime.

Why this priority

Critical severity
EPSS top 4%: very likely to be exploited
Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	9.0 (High)
EPSS exploit chance	12.0% (top 4%)
CISA exploited list	No
Weakness	CWE-94
Published	2009-03-25
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: hannonhill

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2009-03-25 18:30 UTCPublished CVE record published
2026-06-16 23:06 UTCUpdated Record last modified

hannonhill cascade DOWNGRADE

Affected: 5.7 svr

Fixed in: no fixed release known

Safe to downgrade to: a release before 5.7

1. Check installed version

apt-cache policy cascade || rpm -q cascade || cascade --version

2. No fixed release: DOWNGRADE to a release before 5.7 (Debian / Ubuntu)

apt-cache madison cascade sudo apt install cascade=<VERSION_BEFORE_5.7> sudo apt-mark hold cascade

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list cascade sudo dnf downgrade cascade-<VERSION_BEFORE_5.7> sudo dnf versionlock add cascade

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.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: Hannon Hill Cascade Server - (Authenticated) Command Execution

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-2009-1088?

cascade: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2009-1088 being exploited?

CVE-2009-1088 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-2009-1088 affect?

CVE-2009-1088 affects cascade. Severity is high (CVSS 9.0). Hannon Hill Cascade Server 5.7 and other versions allows remote authenticated users to execute arbitrary programs or Java code via a crafted XSLT stylesheet with "extension elements and extension functions" that trigger code execution by Xa

How urgent is CVE-2009-1088?

Priority 61/100. Critical severity; EPSS top 4%: very likely to be exploited; Public exploit reference

Software pages

Java vulnerabilities

References

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