CVE-2026-86712

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.71% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 53.2% of scored records. A rank, not a probability.

NVD base score

8.6 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-09-10.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-09-08 11:23Z1 MO AGO

Last updated

2026-09-10 15:03Z1 MO AGO

Reserved

2026-09-08

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

High (CVSS 8.6)

CNA CVSS vector

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

Weaknesses

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Base

Data version

5.2

Document digest

8666fb1b2ef12f35d0821130f5630c5ebbef415904fe900cbb43e3abfdcd9fdb

• github.comGitHub Security Advisory (GHSA-9rr9-pxr4-gcgc)https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9rr9-pxr4-gcgcvendor-advisory
• github.comPatch Commithttps://github.com/siyuan-note/siyuan/commit/9ce660652de2ced26ec2d98a5a242cb0b8bb7273patch
• github.comSiYuan v3.8.2 Release Noteshttps://github.com/siyuan-note/siyuan/releases/tag/v3.8.2release-notes
• github.comLute.Sanitize runs only in the if (!siyuanHTML) branch, v3.8.1https://github.com/siyuan-note/siyuan/blob/v3.8.1/app/src/protyle/util/paste.tstechnical-description
• github.comhttps://github.com/siyuan-note/siyuanproduct
• www.vulncheck.comVulnCheck Advisory: SiYuan before 3.8.2 Remote Code Execution via Clipboardhttps://www.vulncheck.com/advisories/siyuan-before-3.8.2-remote-code-execution-via-clipboardthird-party-advisory