# CVE-2026-52769: YesWiki SSRF in ActivityPub Signature keyId parsing

Source: https://junglewise.ai/threats/cve-2026-52769-yeswiki-ssrf-in-activitypub-signature-keyid-parsing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-05. Updated: 2026-07-09  
License: CC BY 4.0 with a link back

CVE-2026-52769 · Severity: high · CVSS 8.3 · Published 2026-09-05

YesWiki, a collaborative wiki platform, contains a vulnerability in its ActivityPub integration that allows unauthorized outsiders to force the server to make web requests to arbitrary locations. This can be used to probe internal corporate networks, access private cloud configuration data, or scan for other vulnerable systems that are not normally accessible from the internet. An attacker does not need an account or special permissions to trigger this behavior if the ActivityPub feature is enabled.

Technologies: [yeswiki/yeswiki (Packagist)](https://junglewise.ai/threats/technologies/yeswiki-yeswiki), [YesWiki](https://junglewise.ai/threats/technologies/yeswiki). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist), [YesWiki](https://junglewise.ai/threats/vendors/yeswiki).

## Quick answers

**Is CVE-2026-52769 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52769 being exploited in the wild.

**How severe is CVE-2026-52769?** High severity, with a CVSS score of 8.3, published 5 September 2026.

**Which products and versions are affected?** yeswiki/yeswiki (Packagist) >= 4.6.2, < 4.6.6, ECOSYSTEM:introduced=4.6.2,fixed=4.6.6; YesWiki >= 4.6.2, < 4.6.6.

**Is there a fix for CVE-2026-52769?** Yes. yeswiki/yeswiki (Packagist): upgrade to 4.6.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-52769 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-52769?** Check whether you run yeswiki/yeswiki (Packagist) or YesWiki 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

- yeswiki/yeswiki (Packagist): upgrade to 4.6.6 or later

  ```sh
  composer require yeswiki/yeswiki:^4.6.6
  ```


## Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in YesWiki's ActivityPub implementation, specifically within the `HttpSignatureService::verifySignature()` method. The application processes the `Signature` HTTP header from incoming POST requests to the `/api/forms/{formId}/actor/inbox` route. The `keyId` parameter, which is expected to be a URL pointing to a public key, is fetched via a GET request before any cryptographic verification or URL validation occurs. An unauthenticated remote attacker can provide an arbitrary URL (including internal IP addresses or cloud metadata services like 169.254.169.254) to perform internal port scanning or credential theft. The vulnerability is present when ActivityPub is enabled on at least one Bazar form. This issue is patched in version 4.6.6.

## Affected products

- YesWiki yeswiki/yeswiki >= 4.6.2, < 4.6.6

## Identifiers

- CVE-2026-52769
- GHSA-vw42-752g-5mrp

## Timeline

- 2026-06-02: disclosed
- 2026-07-09: advisory
- 2026-07-09: patched

## References

- [https://api.github.com/users/hash3liZer](https://api.github.com/users/hash3liZer)
- [https://github.com/hash3liZer](https://github.com/hash3liZer)
- [https://api.github.com/users/hash3liZer/gists%7B/gist_id%7D](https://api.github.com/users/hash3liZer/gists%7B/gist_id%7D)
- [https://api.github.com/users/hash3liZer/repos](https://api.github.com/users/hash3liZer/repos)
- [https://avatars.githubusercontent.com/u/29171692?v=4](https://avatars.githubusercontent.com/u/29171692?v=4)
- [https://api.github.com/users/hash3liZer/events%7B/privacy%7D](https://api.github.com/users/hash3liZer/events%7B/privacy%7D)

## Related threats

- [YesWiki SQL injection in despam.php INTERVAL operand](https://junglewise.ai/threats/cve-2026-116828-yeswiki-before-4-7-0-contains-a-sql-injection-vulnerability-in)
- [YesWiki server-side request forgery in Bazar CSV import](https://junglewise.ai/threats/cve-2026-116827-yeswiki-before-4-7-0-contains-a-server-side-request-forgery)
- [YesWiki server-side request forgery in DuplicationManager](https://junglewise.ai/threats/cve-2026-116826-yeswiki-before-4-7-0-contains-a-server-side-request-forgery)
- [YesWiki HTTP Signature replay protection missing in ActivityPub inbox](https://junglewise.ai/threats/cve-2026-116825-yeswiki-from-4-6-2-before-4-7-0-lacks-replay-protection-in)
- [YesWiki stored cross-site scripting in referrers_sites handler](https://junglewise.ai/threats/cve-2026-116824-yeswiki-before-4-7-0-contains-a-stored-cross-site-scripting)