Vulnerability · Published Jul 30, 2026 · Assigned by VulnCheck

CVE-2026-57862Kanboard 1.2.52 and prior SSRF Filter Bypass via Hexadecimal IP Notation

High 8.5

In plain English

A high-severity server-side request forgery in Kanboard from Kanboard. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities).

Severity (CVSS 3.1)8.5High

Exploit odds (30 days)0.4%top 64.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Kanboard 1.2.52 and prior contains a server-side request forgery vulnerability that allows authenticated users to bypass SSRF protections by supplying hexadecimal IP address notation in user-controlled URLs. Attackers can submit hexadecimal-encoded internal IP addresses through the web link creation feature, causing cURL to resolve and connect to internal network resources such as cloud instance metadata services, localhost services, and RFC1918 addresses while the isPrivateURL() filter in app/Core/Http/Client.php incorrectly treats the input as safe due to FILTER_VALIDATE_IP rejecting non-dotted-decimal notation.

Affected products (as reported)

Vendor	Product	Versions
Kanboard	Kanboard	0 – through 1.2.52

Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N

References

Product Repository product
GitHub Gist technical-description
https://www.vulncheck.com/advisories/kanboard-and-prior-ssrf-filter-bypass-via-hexadecimal-ip-notation third-party-advisory