CVE-2026-123201: jarun buku

buku through 5.1.1 SSRF via bukuserver fetch_data and network_handle API

CVSS 6.3 Medium

Published by the CVE Program (CNA: VulnCheck) at 5 Nov 2026, 18:16 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
jarun	buku pkg:pypi/buku	affected 5.1.1 and earlier custom Other versions: unaffected

Identifiers

CVE-2026-123201

CNA

VulnCheck

Weakness (CWE)

CWE-918

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.3	Medium	4.0	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N	CNA (VulnCheck)Used for this record
5.3	Medium	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N	CNA (VulnCheck)

CISA KEV Not listed.
EPSS No score.

Timeline

5 Nov 2026, 18:16 UTC Confirmed by the CVE List
5 Nov 2026, 18:19 UTC First seen by agentprime
5 Nov 2026, 19:17 UTC Confirmed by NVD

Sources

References from the CNA

github.com/jarun/buku/issues/910 issue-tracking
github.com/jarun/buku/pull/916 patchissue-tracking
github.com/jarun/buku/commit/13f6497afc974f02f1069b760772abe8815d1675 patch
github.com/jarun/buku/blob/e232ac357cbba22fe69d6d6dfc0d35512a4cd313/bukuserver/api.py#L97-L105 technical-description
github.com/jarun/buku/blob/e232ac357cbba22fe69d6d6dfc0d35512a4cd313/buku.py#L4057-L4084 technical-description
www.vulncheck.com/advisories/buku-through-5.1.1-ssrf-via-bukuserver-fetch-data-and-network-handle-api third-party-advisory

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.