# CVE-2026-55779: Silverstripe Versioned provides versioning for Silverstripe models. Prior to 3.2.1, RestoreAction::getRestoreMessage() in src/RestoreAction.

Source: https://junglewise.ai/threats/cve-2026-55779-silverstripe-versioned-xss-in-archive-admin-restore  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-28. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-55779 · Severity: medium · CVSS 5.4 · Published 2026-08-28

Silverstripe versioned is a content versioning system for the Silverstripe CMS platform. The archive admin restore feature allows administrators to restore previously archived pages, but fails to properly sanitize page titles before displaying them, allowing attackers to inject malicious JavaScript code. An attacker who can create or modify a page title could execute arbitrary actions in an administrator's browser when they attempt to restore that page, potentially leading to account compromise or data manipulation.

Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist), [Silverstripe](https://junglewise.ai/threats/vendors/silverstripe).

## Quick answers

**Is CVE-2026-55779 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55779 being exploited in the wild.

**How severe is CVE-2026-55779?** Medium severity, with a CVSS score of 5.4, published 28 August 2026.

**Which products and versions are affected?** silverstripe/versioned (Packagist) < 3.2.1, ECOSYSTEM:introduced=0,fixed=3.2.1; Silverstripe Versioned < 3.2.1.

**Is there a fix for CVE-2026-55779?** Yes. silverstripe/versioned (Packagist): upgrade to 3.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-55779 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-55779?** Check whether you run silverstripe/versioned (Packagist) or Silverstripe Versioned at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- silverstripe/versioned (Packagist): upgrade to 3.2.1 or later

  ```sh
  composer require silverstripe/versioned:^3.2.1
  ```


## Technical details

The vulnerability is a cross-site scripting (XSS) flaw in the RestoreAction message handler within Silverstripe versioned. The root cause is insufficient input sanitization of page titles when rendering restoration confirmation messages in the ArchiveAdmin interface. The attack vector is network-based and requires user interaction—specifically, an administrator must initiate a page restore operation. The vulnerability allows an attacker to execute arbitrary JavaScript within the security context of the administrator's authenticated session, with potential impacts including session hijacking, unauthorized actions, or data exfiltration. The issue was patched in version 3.2.1, released on June 24, 2026.

## Affected products

- Silverstripe Ltd. versioned < 3.2.1

## Identifiers

- CVE-2026-55779
- GHSA-m4g4-86qc-v8w7

## Timeline

- 2026-06-24: disclosed: Vulnerability published to GitHub Advisory Database
- 2026-06-24: patched: Version 3.2.1 released with fix

## References

- [https://github.com/silverstripe/silverstripe-versioned/security/advisories/GHSA-m4g4-86qc-v8w7](https://github.com/silverstripe/silverstripe-versioned/security/advisories/GHSA-m4g4-86qc-v8w7)
- [https://github.com/silverstripe/silverstripe-versioned/pull/541](https://github.com/silverstripe/silverstripe-versioned/pull/541)
- [https://github.com/silverstripe/silverstripe-versioned/commit/6e30a2cf8d4b9233690464da61bd0fc4d3e92952](https://github.com/silverstripe/silverstripe-versioned/commit/6e30a2cf8d4b9233690464da61bd0fc4d3e92952)
- [https://github.com/FriendsOfPHP/security-advisories/blob/master/silverstripe/versioned/CVE-2026-55779.yaml](https://github.com/FriendsOfPHP/security-advisories/blob/master/silverstripe/versioned/CVE-2026-55779.yaml)
- [https://github.com/silverstripe/silverstripe-versioned/releases/tag/3.2.1](https://github.com/silverstripe/silverstripe-versioned/releases/tag/3.2.1)
- [https://www.silverstripe.org/download/security-releases/cve-2026-55779](https://www.silverstripe.org/download/security-releases/cve-2026-55779)