CVE-2026-57862 json
Kanboard 1.2.52 and prior SSRF Filter Bypass via Hexadecimal IP Notation
published 2026-07-30 3 mo ago modified 2026-09-24 46 d ago also EUVD-2026-51164
- cvss
- 8.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 35%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3 mo ago
Exploit prediction
0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- gist.github.com https://gist.github.com/sermikr0/67c8acfc395e465127e729dc309da3ae referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N |
| CNA | 3.1 | 8.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N |
| CNA | 4.0 | 8.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Kanboard Kanboard
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
gist.github.com
/sermikr0/67c8acfc395e465127e729dc309da3ae
technical-description, exploit
-
github.com
/kanboard/kanboard
product
-
vulncheck.com
/advisories/kanboard-and-prior-ssrf-filter-bypass-via-hexadecimal-ip-notation
third-party-advisory
Sources
- CVE List CVE-2026-57862
- NVD CVE-2026-57862
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