Vulnerability · Published Jun 9, 2026 · Assigned by VulnCheck
CVE-2026-50635LimeSurvey Password Reset Host Header Injection Discloses Reset Token
High 8.8
In plain English
A high-severity security flaw in LimeSurvey from LimeSurvey. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities).
Official description
LimeSurvey constructs account password-reset links from the client-supplied HTTP Host header without validating it. The optional allowedHosts allowlist that would constrain this is undefined in the default (and documented) configuration, so LSHttpRequest::checkIsAllowedHost() results in no operation. A remote, unauthenticated attacker who submits a forgotten-password request for a known account (requiring only the target's username and email) with a spoofed Host header causes LimeSurvey to email that account a reset link whose hostname is attacker-controlled while embedding the genuine validation_key. When the recipient or an automated inbound mail-security link scanner dereferences the link, the valid reset token is disclosed to the attacker, who replays it against the legitimate host's newPassword endpoint to set a new password and take over the account.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | limesurvey/limesurvey | no fix listed | GHSA-5c37-5j7w-8mh8 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| LimeSurvey | LimeSurvey | 0 – through 7.0 |
Weakness: CWE-640 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
References
- GitHub Pull Request 5032 issue-tracking
- Official Product Homepage product
- VulnCheck Advisory: LimeSurvey Password Reset Host Header Injection Discloses Reset Token third-party-advisory