Is there a public exploit for CVE-2026-126776?

No public exploit for CVE-2026-126776 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-126776?

CVE-2026-126776 scores CVSS 6 (v4.0), rated medium.

What does CVE-2026-126776 affect?

CVE-2026-126776 affects siyuan-note SiYuan.

6.0 Medium

SiYuan 3.7.0 before 3.8.10 on Windows contains a path traversal vulnerability in kernel/util/webfetch.go that allows attackers to write…

CVE-2026-126776

SiYuan 3.7.0 before 3.8.10 on Windows contains a path traversal vulnerability in kernel/util/webfetch.go that allows attackers to write files outside the import directory via backslash-encoded filenames. Attackers controlling a URL fetched by the MCP webfetch or httprequest tools can use %5C-encoded ..\ sequences to write chosen response bytes to directories above temp/import that are writable by the SiYuan user.

Assessment

CVSS: 6 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 11 November 2026
Last updated: 11 November 2026
Affected: siyuan-note · SiYuan
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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