How severe is CVE-2026-29183?

CVE-2026-29183 has a CVSS score of 9.3/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-29183?

CVE-2026-29183 affects the following packages: github.com/siyuan-note/siyuan/kernel (Go). Ecosystems affected: Go.

How do I fix CVE-2026-29183?

Update github.com/siyuan-note/siyuan/kernel to 0.0.0-20260304034809-d68bd5a79391 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-29183 is resolved across your whole dependency graph.

How do I detect CVE-2026-29183 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/siyuan-note/siyuan/kernel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-29183 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2026-29183 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-29183 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-29183?

CVE-2026-29183 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 53th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-29183?

CVE-2026-29183 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Is there exploit tooling available for CVE-2026-29183?

A Nuclei detection template exists for CVE-2026-29183, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2026-29183 published, and has it been updated?

CVE-2026-29183 was published on March 6, 2026 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

CRITICAL severity

CVE-2026-29183 — kernel

CRITICALFix: siyuan-note/siyuan@d68bd5a

CVE-2026-29183 is a critical-severity (CVSS 9.3) Cross-site Scripting (XSS) vulnerability in github.com/siyuan-note/siyuan/kernel. A fix is available for github.com/siyuan-note/siyuan/kernel — see the affected versions and patch details below.

SiYuan: Unauthenticated reflected SVG XSS in `/api/icon/getDynamicIcon` (`type=8`) enables arbitrary JavaScript execution

Also known asGHSA-6865-qjcf-286fGO-2026-4596

Published

Mar 6, 2026

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-29183.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs53th percentile — riskier than 53% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐹github.com/siyuan-note/siyuan/kernel

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Summary

An unauthenticated reflected XSS vulnerability exists in the dynamic icon API endpoint:

GET /api/icon/getDynamicIcon

When type=8, attacker-controlled content is embedded into SVG output without escaping. Because the endpoint is unauthenticated and returns image/svg+xml, a crafted URL can inject executable SVG/HTML event handlers (for example onerror) and run JavaScript in the SiYuan web origin.

This can be chained to perform authenticated API actions and exfiltrate sensitive data when a logged-in user opens the malicious link.

Details

The issue is caused by unsafe output construction and incomplete sanitization:

Endpoint is exposed without auth middleware
- Source: https://github.com/siyuan-note/siyuan/blob/master/kernel/api/router.go#L27-L37
- GET /api/icon/getDynamicIcon is registered in the unauthenticated section.
User input is inserted into SVG via string formatting
- Source: https://github.com/siyuan-note/siyuan/blob/master/kernel/api/icon.go#L115-L175
- Source: https://github.com/siyuan-note/siyuan/blob/master/kernel/api/icon.go#L537-L585
- In generateTypeEightSVG, %s directly injects content into <text>...</text> without XML/HTML escaping.
Sanitizer only removes <script> tags
- Source: https://github.com/siyuan-note/siyuan/blob/master/kernel/util/misc.go#L235-L281
- RemoveScriptsInSVG removes <script> nodes, but does not remove dangerous attributes (onerror, onload, etc.) or unsafe elements.

As a result, payloads such as </text><image ... onerror=...><text> survive and execute.

PoC

Minimal browser execution PoC

Open this URL in a browser:

GET /api/icon/getDynamicIcon?type=8&content=%3C%2Ftext%3E%3Cimage%20href%3Dx%20onerror%3Dalert(document.domain)%3E%3C%2Fimage%3E%3Ctext%3E

Example full URL:

http://127.0.0.1:6806/api/icon/getDynamicIcon?type=8&content=%3C%2Ftext%3E%3Cimage%20href%3Dx%20onerror%3Dalert(document.domain)%3E%3C%2Fimage%3E%3Ctext%3E

Expected result:

JavaScript executes (alert(document.domain)), confirming reflected XSS.

Authenticated impact demonstration

If a victim is authenticated in the same browser session, JavaScript running in origin can call privileged APIs and exfiltrate returned data.

Impact

This is a reflected XSS in an unauthenticated endpoint, with realistic account/data compromise impact:

Arbitrary JavaScript execution in SiYuan web origin.
Authenticated action abuse via same-origin API calls.
Sensitive data exposure (notes/config/API responses) from victim context.
Potential chained server-impact actions depending on victim privileges and deployment mode.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/siyuan-note/siyuan/kernel`	all versions	0.0.0-20260304034809-d68bd5a79391`go get github.com/siyuan-note/siyuan/kernel@v0.0.0-20260304034809-d68bd5a79391`

Affected Products

1 product · 1 configurations

Application

siyuanb3log

< 3.5.9

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/siyuan-note/siyuan/kernel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/siyuan-note/siyuan/kernel to 0.0.0-20260304034809-d68bd5a79391 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-29183 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

How to detect CVE-2026-29183

A community-maintained Nuclei template exists for this CVE. You can scan for it directly:

nuclei -id cve-2026-29183 -u https://target

Template: SiYuan Note - Cross-Site Scripting
Severity: medium
Impact: Successful exploitation allows arbitrary JavaScript execution in the SiYuan web origin. Attackers can abuse authenticated API actions and exfiltrate sensitive data if a privileged session is active.
Remediation: Upgrade to SiYuan version 3.5.9 or later, which properly sanitizes SVG content.

Template by ProjectDiscovery nuclei-templates (ritikchaddha), MIT licensed. View the full template. Scan only systems you are authorised to test.

Frequently Asked Questions

### Summary An unauthenticated reflected XSS vulnerability exists in the dynamic icon API endpoint: - `GET /api/icon/getDynamicIcon` When `type=8`, attacker-controlled `content` is embedded into SVG output without escaping. Because the endpoint is unauthenticated and returns `image/svg+xml`, a crafted URL can inject executable SVG/HTML event handlers (for example `onerror`) and run JavaScript in the SiYuan web origin. This can be chained to perform authenticated API actions and exfiltrate sensitive data when a logged-in user opens the malicious link. ### Details The issue is caused by unsa

O3 Security · Impact-Aware SCA

Is CVE-2026-29183 in your dependencies?

Find it across Go, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

9.3/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

Timeline

Disclosed

Mar 6, 2026

Last updated

Oct 28, 2026

Identifiers

CVE-2026-29183

GHSA-6865-qjcf-286f

GO-2026-4596

References

Advisorygithub.com · CVE 2026 29183.json Advisorygithub.com · GHSA 6865 qjcf 286f Advisorynvd.nist.gov · CVE 2026 29183 Webgithub.com · d68bd5a79391742b3cb2e14d892bdd9997064927 Packagegithub.com · siyuan

Related vulnerabilities

This CVE is critical severity — higher than any of the other 8 CVEs affecting kernel (highest there: high).

CVE-2026-60083CVE-2026-73630CVE-2026-73054CVE-2026-73049CVE-2026-62204GHSA-xp3q-r38w-vgqmGHSA-3cm4-ccvw-6xr6GHSA-4wwp-f6gw-6qm5

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 28, 2026