SSRF in Jarun Buku
CVE-2026-123201
Buku (bukuserver) through 5.1.1 contains an unauthenticated server-side request forgery vulnerability that allows remote attackers to make the server request internal hosts by supplying a url parameter to /api/fetch_data or /api/network_handle. Attackers can target loopback, private, or cloud metadata IP addresses, which pass the weak is_bad_url() check and follow redirects, to discover internal services and read their page titles, descriptions, and keywords.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/jarun/buku/blob/e232ac357cbba22fe69d6d6dfc0d35512a4cd313/buku.py (technical-description)
- github.com/jarun/buku/blob/e232ac357cbba22fe69d6d6dfc0d35512a4cd313/bukuserver/… (technical-description)
- github.com/jarun/buku/commit/13f6497afc974f02f1069b760772abe8815d1675 (patch)
- github.com/jarun/buku/issues/910 (issue-tracking)
- github.com/jarun/buku/pull/916 (issue-tracking, patch)
- VulnCheck Advisory: buku through 5.1.1 SSRF via bukuserver fetch_data and network_handle API (third-party-advisory)
Frequently asked questions
- What is CVE-2026-123201?
- CVE-2026-123201 is a medium-severity vulnerability in Jarun Buku, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.3/10. Published 2026-11-05.
- How severe is CVE-2026-123201?
- Medium severity. CVSS v3 base score is 5.3 out of 10.