How severe is CVE-2026-30587?

CVE-2026-30587 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-30587 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-30587?

CVE-2026-30587 primarily affects Seafile Seafile Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-30587?

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

Does CVE-2026-30587 have an EU (EUVD) identifier?

Yes. CVE-2026-30587 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-15940.

When was CVE-2026-30587 published?

CVE-2026-30587 was published on 2026-03-25 and last updated on 2026-06-17.

CVE-2026-30587

CVE-2026-30587 is a high-severity vulnerability in Seafile Seafile Server with a CVSS 3.x base score of 8.7. 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: High (CVSS 3.x base score 8.7)
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-15940
Weakness: CWE-79
Affected product: Seafile Seafile Server
Published: 2026-03-25
Last modified: 2026-06-17

Description

Multiple Stored XSS vulnerabilities exist in Seafile Server version 13.0.15,13.0.16-pro,12.0.14 and prior and fixed in 13.0.17, 13.0.17-pro, and 12.0.20-pro, via the Seadoc (sdoc) editor. The application fails to properly sanitize WebSocket messages regarding document structure updates. This allows authenticated remote attackers to inject malicious JavaScript payloads via the src attribute of embedded Excalidraw whiteboards or the href attribute of anchor tags

Frequently asked questions

What is CVE-2026-30587?: Multiple Stored XSS vulnerabilities exist in Seafile Server version 13.0.15,13.0.16-pro,12.0.14 and prior and fixed in 13.0.17, 13.0.17-pro, and 12.0.20-pro, via the Seadoc (sdoc) editor. The application fails to properly sanitize WebSocket messages regarding document structure updates. This allows authenticated remote attackers to inject malicious JavaScript payloads via the src attribute of embedded Excalidraw whiteboards or the href attribute of anchor tags
How severe is CVE-2026-30587?: CVE-2026-30587 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-30587 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-30587?: CVE-2026-30587 primarily affects Seafile Seafile Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-30587?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-30587 have an EU (EUVD) identifier?: Yes. CVE-2026-30587 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-15940.
When was CVE-2026-30587 published?: CVE-2026-30587 was published on 2026-03-25 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:seafile:seafile_server:*:*:*:*:professional:*:*:*
cpe:2.3:a:seafile:seafile_server:13.0.15:*:*:*:community:*:*:*
cpe:2.3:a:seafile:seafile_server:13.0.16:*:*:*:professional:*:*:*

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