Is CVE-2026-42556 in the CISA KEV catalog?

No. CVE-2026-42556 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-42556?

CVE-2026-42556 has a CVSS v3 base score of 8.9 (HIGH).

What is the EPSS score for CVE-2026-42556?

CVE-2026-42556 has an EPSS score of 0.26% (17th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2026-42556

HIGH

8.9

CVSS v3

NVD

Description

Postiz is an AI social media scheduling tool. From version 2.21.6 to before version 2.21.7, any authenticated user who can create a post can store arbitrary HTML in post content by tampering their own save request and send the public preview link /p/<postId>?share=true to another user. The preview page renders that stored HTML with dangerouslySetInnerHTML on the main application origin. This issue has been patched in version 2.21.7.

CWE-79Cross-Site Scripting (XSS)

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionRequired

ScopeChanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityLow

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

Exploit Intelligence

0.26%probability of exploitation in 30 days

17thpercentile

Low risk: more likely to be exploited than 17% of all known CVEs.

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-18.