CVE-2026-123201

MEDIUM 5.3

buku through 5.1.1 SSRF via bukuserver fetch_data and network_handle API

CVSS Score

5.3

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-918
Vendor	jarun
Product	buku
Published	Nov 5, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Affected Versions

jarun / buku

0 ≤ 5.1.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/jarun/buku/issues/910 github.com: https://github.com/jarun/buku/pull/916 github.com: https://github.com/jarun/buku/commit/13f6497afc974f02f1069b760772abe8815d1675 github.com: https://github.com/jarun/buku/blob/e232ac357cbba22fe69d6d6dfc0d35512a4cd313/bukuserver/api.py#L97-L105 github.com: https://github.com/jarun/buku/blob/e232ac357cbba22fe69d6d6dfc0d35512a4cd313/buku.py#L4057-L4084 vulncheck.com: https://www.vulncheck.com/advisories/buku-through-5.1.1-ssrf-via-bukuserver-fetch-data-and-network-handle-api

Credits

George Chen LeXofLeviafan