Is there a public exploit for CVE-2026-126265?

No public exploit for CVE-2026-126265 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-2026-126265?

CVE-2026-126265 scores CVSS 9.1 (v4.0), rated critical.

What does CVE-2026-126265 affect?

CVE-2026-126265 affects siyuan-note SiYuan.

9.1 Critical

SiYuan 2.1.0 before 3.8.9 contains a flaw where the loginAuth CAPTCHA challenge lives in a signed client-side cookie, allowing reuse of a…

CVE-2026-126265

SiYuan 2.1.0 before 3.8.9 contains a flaw where the loginAuth CAPTCHA challenge lives in a signed client-side cookie, allowing reuse of a solved challenge. Attackers can replay the original signed siyuan cookie with distinct wrong access codes to brute-force the code and gain an administrator session.

Assessment

CVSS: 9.1 (v4.0)
Severity: Critical
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 13 November 2026
Last updated: 13 November 2026
Affected: siyuan-note · SiYuan
Assigner: VulnCheck

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

At the source

EUVD (ENISA)

References

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