CVE-2026-72811: github.com/siyuan-note/siyuan/kernel (Go)

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
EPSS 0.4%, percentile 37: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 37% of all scored CVEs (low). EPSS is a probability, not a verdict.
Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
Only applies if your dependency tree includes github.com/siyuan-note/siyuan/kernel (Go) < 0.0.0-20260723004839-1a5b3431d5ab, fixed in 0.0.0-20260723004839-1a5b3431d5ab. Check your lockfile, including transitive dependencies.

What it is

SiYuan versions

From the GitHub advisory

CVE: This vulnerability corresponds to CVE-2026-72811.

Summary

The backlink/mention search query (kernel/model/backlink.go) concatenates stored block metadata (title, name, alias, anchor text) and the client-supplied keyword into a SQL MATCH/search statement, escaping only the double-quote character (") and not the single quote ('). A single quote in either the client keyword or in stored document metadata breaks out of the string literal. The query runs on the main read-write siyuan.db handle through a statement-stacking-capable driver.

This yields two vectors: - First-order: a client-supplied keyword containing ' injects directly. This path is reachable by an anonymous reader on the publish surface. - Second-order: a document whose title/name/alias contains ' is stored safely (indexing uses parameterized inserts) but detonates when that stored value is later concatenated into the backlink query including on another user's kernel that has ingested the malicious document.

Details

Weakness type: CWE-89.

Product: github.com/siyuan-note/siyuan/kernel (Go) · Assigned by: VulnCheck · Published: 2026-08-14

Affected and fixed versions

Ecosystem	Package	Vulnerable	First fixed
Go	`github.com/siyuan-note/siyuan/kernel`	< 0.0.0-20260723004839-1a5b3431d5ab	0.0.0-20260723004839-1a5b3431d5ab

Vendor	Product	Affected versions (per CVE record)
siyuan-note	siyuan	< 3.7.4

Severity scores

Scored by	CVSS	Score	Vector
VulnCheck	4.0	9.9 Critical	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N`
VulnCheck	3.1	10 Critical	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N`
GitHub	3.1	10.0	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N`

Attack vector: network (remotely reachable)
Attack complexity: low
Attack requirements: none
Privileges required: none (no login)
User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
FIRST EPSS (model of 2026-10-21): 0.44% probability of exploitation activity in the next 30 days; percentile 37.

Timeline

2026-08-14 — CVE record last updated
2026-08-14 — CVE record published by VulnCheck
2026-09-03 — GitHub-reviewed advisory GHSA-q2vg-7qgx-x5fc published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.