CVE-2026-77871
Post Snippets <= 4.2.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes
- Published
- Updated
- Reserved
- Assigned by
- Wordfence
Description
The Post Snippets – Custom WordPress Code Snippets Customizer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Shortcode Attributes in all versions up to, and including, 4.2.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Entity-encoded payloads such as <script>...</script> survive WordPress's wp_kses_post on-save sanitization because kses does not decode HTML entities, and are only converted back into executable HTML tags at render time by the plugin's own shortcode filter. This requires snippet shortcodes to be enabled.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| WordfenceCNA (assigner) | 3.1 | Medium6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.24% · top 85% of all CVEs (5 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.4.
Weakness
Affected products
saadiqbal · Post Snippets – Custom WordPress Code Snippets Customizer
- affected ≤ 4.2.4
References (10)
- https://www.wordfence.com/threat-intel/vulnerabilities/id/a46c37f4-245d-423f-bdad-296fdf377ecc?source=cve (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.3/src/PostSnippets/Shortcode.php#L183 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.4/src/PostSnippets/Shortcode.php#L183 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.4/src/PostSnippets/Shortcode.php#L140 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.4/src/PostSnippets/Shortcode.php#L70 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.4/src/PostSnippets/Shortcode.php#L29 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.3/src/PostSnippets/Shortcode.php#L140 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.3/src/PostSnippets/Shortcode.php#L70 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/post-snippets/tags/4.2.3/src/PostSnippets/Shortcode.php#L29 (opens in a new tab)
- https://plugins.trac.wordpress.org/changeset/3759640/post-snippets/trunk/src/PostSnippets/Shortcode.php (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-77871)Record last updated .