Vulnerability · Published Oct 16, 2026 · Assigned by VulnCheck

CVE-2026-111626Webreaper Damselfly through 4.5.3 Missing Authentication on REST API Controllers

Critical 9.8

In plain English

A critical-severity missing authentication in Damselfly from Webreaper. 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 39% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)0.4%top 61.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Webreaper Damselfly through 4.5.3 contains an authentication bypass vulnerability that allows unauthenticated attackers to access all /api/* routes because controller authorization attributes are commented out. Attackers can send PUT /api/users with Admin roles to create administrator accounts, or POST /api/users to reset any user's password, gaining full control.

Affected products (as reported)

Vendor	Product	Versions
Webreaper	Damselfly	0 – through 4.5.3

Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

https://hackmd.io/@hieuPenguinnn/damselfly-api-missing-authorization third-party-advisory
https://github.com/Webreaper/Damselfly/blob/4.5.3/Damselfly.Web.Server/Controllers/UserManagementController.cs#L8-L53 technical-description
https://github.com/Webreaper/Damselfly/blob/4.5.3/Damselfly.Web.Server/Program.cs#L238-L242 technical-description
https://github.com/Webreaper/Damselfly/issues/409 issue-tracking
VulnCheck Advisory: Webreaper Damselfly through 4.5.3 Missing Authentication on REST API Controllers third-party-advisory