XSS in Silverstripe Silverstripe-Versioned
CVE-2026-55779
Silverstripe Versioned provides versioning for Silverstripe models. Prior to 3.2.1, RestoreAction::getRestoreMessage() in src/RestoreAction.php builds ArchiveAdmin restore notifications rendered as CAST_HTML and inserts $restoredItem->Title, $restoredItem->URLSegment, $restoredItem->CMSEditLink(), and $changedProperty['value'] without applying Convert::raw2xml(). When an administrator restores an archived page containing a crafted title or URL segment, the generated restoration message can execute stored JavaScript in the administrator's browser, compromising the confidentiality and integrity of the CMS session. This issue is fixed in version 3.2.1.
Vulnerability class: XSS (Cross-Site Scripting)
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N.
Affected products
- Silverstripe Silverstripe-versioned — versions < 3.2.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-55779?
- CVE-2026-55779 is a medium-severity vulnerability in Silverstripe Silverstripe-Versioned, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-08-28.
- How severe is CVE-2026-55779?
- Medium severity. CVSS v3 base score is 5.4 out of 10.