CVE-2026-88991: CVE-2026-88991 - RCE in email subject field via template execution

unknown Affects silverstripe/userforms. Feed 2026.11.09.1, updated 2026-11-08; CVE published 2026.

CVE-2026-88991 - RCE in email subject field via template execution

Package: silverstripe/userforms Composer
Affected versions: <6.4.10 or >=7.0.0 and <7.1.4
Fixed in: 6.4.10, 7.1.4
Severity: unknown
Exploitation: not on CISA KEV
Source: friendsofphp

References

https://www.silverstripe.org/download/security-releases/cve-2026-88991

NVD record silverstripe/userforms advisories

Am I affected?

Find out in one command. phpwarden checks your composer.lock against this advisory and 20,000+ others, ranked by real-world exploitation (CISA KEV + EPSS). Free, offline, open data.

# PHP projects (recommended)
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Related advisories

CVE-2020-9280 high SilverStripe Folders migrated from 3.x may be unsafe to upload to same package: silverstripe/userforms
CVE-2026-54721 high silverstripe/userforms vulnerable to remote code execution via userforms email subject same package: silverstripe/userforms
GHSA-55pp-293f-3365 medium silverstripe/userforms file upload exposure on UserForms module same package: silverstripe/userforms
CVE-2026-88992 unknown CVE-2026-88992 - Userforms CSV export restricted file access same package: silverstripe/userforms
CVE-2026-91111 unknown CVE-2026-91111 - Uploaded XML XSS same package: silverstripe/userforms
SS-2015-018-1 unknown SS-2015-018: File upload exposure on UserForms module same package: silverstripe/userforms