Zero Spam for WordPress <= 5.7.10 - Unauthenticated Stored Cross-Site Scripting via Nested POST Array Keys via Contact Form 7 Integration

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

The Zero Spam for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Nested POST Array Keys via Contact Form 7 Integration in all versions up to, and including, 5.7.10 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload is delivered by submitting a Contact Form 7 request with a nested POST array key containing arbitrary HTML or JavaScript — PHP parses the field name into a nested array key, which is stored verbatim in the zerospam_log.submission_data column when Zero Spam flags the submission as spam due to the absence of the zerospam_david_walsh_key field.

Source published

25 Sep 2026 07:40:23 UTC

Source modified

25 Sep 2026 10:34:21 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N