# CVE-2026-109310: SiYuan v3.1.12 before v3.8.6 Denial of Service via getDynamicIcon Template

> Attackers can cause denial of service via resource exhaustion in SiYuan's dynamic icon API, affecting all users unless patched.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Oct 2026
- **Updated:** 13 Oct 2026
- **Also known as:** GHSA-cxwr-r7cq-xw52, GHSA-q79h-f459-w43f

## What is CVE-2026-109310?

CVE-2026-109310 is a high-severity denial of service vulnerability in siyuan-note siyuan, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

SiYuan v3.1.12 before v3.8.6 fails to restrict the Sprig template function map in the /api/icon/getDynamicIcon content parameter, allowing resource exhaustion. A publish reader, or anyone when publish auth is disabled, can use uncapped functions like until to OOM-kill the kernel with one request.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-109310?


## How do I fix CVE-2026-109310?

No fix has been published for CVE-2026-109310 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-109310 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109310 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-109310 and fix it if it is affected.

What it is: CVE-2026-109310 is a high-severity denial of service vulnerability in siyuan-note siyuan, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109310 exists.

Affected product: siyuan-note siyuan. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-109310/ (Markdown: https://insights.sbomify.com/CVE-2026-109310/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-109310
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-109310
- OSV: https://osv.dev/vulnerability/CVE-2026-109310

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-109310/
Summaries are generated and may contain mistakes; the official description above is the record.