Description
A URL parameter injection vulnerability was found in the back-channel ticket validation step of the CAS protocol in Jasig Java CAS Client before 3.3.2, .NET CAS Client before 1.0.2, and phpCAS before 1.3.3 that allow remote attackers to inject arbitrary web script or HTML via the (1) service parameter to validation/AbstractUrlBasedTicketValidator.java or (2) pgtUrl parameter to validation/Cas20ServiceTicketValidator.java.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | php-cas | 1.3.3-1 | — |
| Debian 13 | php-cas | 1.3.3-1 | — |
| Debian 12 | php-cas | 1.3.3-1 | — |
| Debian 7 | php-cas | 1.3.1-4+deb7u1 | DSA-3017-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.jasig.cas:cas-client | < 3.3.2 | 3.3.2 | GHSA-9fc5-q25c-r2wr |
| NuGet | DotNetCasClient | < 1.0.2 | 1.0.2 | GHSA-9fc5-q25c-r2wr |
| Packagist | jasig/phpcas | < 1.3.3 | 1.3.3 | GHSA-9fc5-q25c-r2wr |
Advisories 1
- DSA-3017-1 php-cas - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1131350
- https://www.mail-archive.com/cas-user%40lists.jasig.org/msg17338.html
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=759718
- https://github.com/Jasig/dotnet-cas-client/commit/f0e030014fb7a39e5f38469f43199dc590fd0e8d
- https://github.com/Jasig/java-cas-client/commit/ae37092100c8eaec610dab6d83e5e05a8ee58814
- https://github.com/Jasig/phpCAS/blob/master/docs/ChangeLog
- https://github.com/Jasig/phpCAS/pull/125
- https://issues.jasig.org/browse/CASC-228
- https://www.debian.org/security/2014/dsa-3017.en.html
- http://lists.fedoraproject.org/pipermail/package-announce/2014-August/137182.html
- https://exchange.xforce.ibmcloud.com/vulnerabilities/95673