How severe is CVE-2026-29183?

CVE-2026-29183 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-29183 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-29183?

CVE-2026-29183 affects B3log Siyuan. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-29183?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-29183 have an EU (EUVD) identifier?

Yes. CVE-2026-29183 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10023.

When was CVE-2026-29183 published?

CVE-2026-29183 was published on 2026-03-06 and last updated on 2026-06-17.

CVE-2026-29183

CVE-2026-29183 is a critical-severity vulnerability in B3log Siyuan with a CVSS 3.x base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Critical (CVSS 3.x base score 9.3)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-10023
Weakness: CWE-79
Affected product: B3log Siyuan
Published: 2026-03-06
Last modified: 2026-06-17

Description

SiYuan is a personal knowledge management system. Prior to version 3.5.9, 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. This issue has been patched in version 3.5.9.

Frequently asked questions

What is CVE-2026-29183?: SiYuan is a personal knowledge management system. Prior to version 3.5.9, 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. This issue has been patched in version 3.5.9.
How severe is CVE-2026-29183?: CVE-2026-29183 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-29183 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-29183?: CVE-2026-29183 affects B3log Siyuan. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-29183?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-29183 have an EU (EUVD) identifier?: Yes. CVE-2026-29183 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10023.
When was CVE-2026-29183 published?: CVE-2026-29183 was published on 2026-03-06 and last updated on 2026-06-17.

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-6865-qjcf-286f

Affected products (1)

cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*

More vulnerabilities in B3log Siyuan

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