# CVE-2026-55840: Erudika Scoold open redirect in authentication callback

Source: https://junglewise.ai/threats/cve-2026-55840-scoold-is-a-q-a-and-a-knowledge-sharing-platform-for-teams-prior  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-15. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-55840 · Severity: medium · CVSS 5.4 · Published 2026-10-15

Scoold is a team-based Q&A and knowledge-sharing platform. An attacker can craft a malicious sign-in link that redirects users to an attacker-controlled website after they authenticate, enabling phishing attacks and credential theft without any user awareness.

Technologies: [Erudika Scoold](https://junglewise.ai/threats/technologies/scoold). Vendors: [Erudika](https://junglewise.ai/threats/vendors/erudika).

## Quick answers

**Is CVE-2026-55840 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55840 being exploited in the wild.

**How severe is CVE-2026-55840?** Medium severity, with a CVSS score of 5.4, published 15 October 2026.

**Which products and versions are affected?** Erudika Scoold before 1.69.1.

**Is there a fix for CVE-2026-55840?** Yes: fixed in 1.69.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-55840 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-55840?** Check whether you run Erudika Scoold 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

- Fixed in 1.69.1

## Technical details

The getBackToUrl() method in HttpUtils.java performs insufficient URL validation using a simple prefix check against the configured server hostname. An attacker can supply an absolute URL whose hostname begins with the legitimate hostname (e.g., "legit.comattacker.com") to bypass the check, as URI.resolve() retains the attacker-controlled URL. This allows post-authentication redirects to arbitrary attacker-controlled domains, enabling phishing and token theft.

## Affected products

- Erudika Scoold before 1.69.1

## Timeline

- 2026-10-15: disclosed

## References

- [https://github.com/Erudika/scoold/commit/9d61f6fe15d4f9f6262812ba7fea43be8d5bb745](https://github.com/Erudika/scoold/commit/9d61f6fe15d4f9f6262812ba7fea43be8d5bb745)
- [https://github.com/Erudika/scoold/releases/tag/1.69.1](https://github.com/Erudika/scoold/releases/tag/1.69.1)

## Related threats

- [Scoold authentication bypass in API configuration endpoints](https://junglewise.ai/threats/cve-2026-57183-scoold-is-a-q-a-and-a-knowledge-sharing-platform-for-teams-prior)
- [Scoold CORS misconfiguration allows cross-site request forgery](https://junglewise.ai/threats/cve-2026-55842-scoold-is-a-q-a-and-a-knowledge-sharing-platform-for-teams-prior)
- [Erudika Scoold privilege escalation in private spaces](https://junglewise.ai/threats/cve-2026-54677-erudika-scoold-privilege-escalation-in-private-spaces)
- [Scoold API authorization bypass in question replies](https://junglewise.ai/threats/cve-2026-54676-scoold-api-authorization-bypass-in-question-replies)
- [Erudika Scoold privilege escalation via configuration overwrite](https://junglewise.ai/threats/cve-2026-42176-erudika-scoold-privilege-escalation-via-configuration-overwrite)