CVE-2026-13253Post Grid Gutenberg Blocks for News, Magazines, Blog Websites <= 5.0.31 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'moreResultsText' Block Attribute
- 6.4MediumCVSS base score
- 0.36%Exploitation in 30 daysEPSS · top 70% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
The Ultimate Post plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'moreResultsText' block attribute of the ultimate-post/advanced-search block in versions up to and including 5.0.31. This is due to insufficient input sanitization and output escaping in the Advanced_Search::content() render callback: the attribute value is filtered with wp_kses(), which strips disallowed HTML tags but does NOT escape HTML special characters such as double quotes in plain text, and the result is then concatenated directly into the data-viewmoretext HTML attribute without esc_attr(). 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.
Timeline
ID reserved
By Wordfence
- 15 days later
· 15 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
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)
- 0.36% · top 70% of all CVEs (15 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.
Affected products
wpxpo · Post Grid Gutenberg Blocks – PostX
- affected ≤ 5.0.31
References
References8
- https://www.wordfence.com/threat-intel/vulnerabilities/id/070ccd70-22c3-47f1-9dce-a884bff9ea76?source=cve (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.27/blocks/Advanced_Search.php#L116 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.28/blocks/Advanced_Search.php#L116 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.28/blocks/Advanced_Search.php#L108 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.28/classes/Blocks.php#L231 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.27/blocks/Advanced_Search.php#L108 (opens in a new tab)
- https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.27/classes/Blocks.php#L231 (opens in a new tab)
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3598669%40ultimate-post&new=3598669%40ultimate-post (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)
- EUVD EUVD-2026-42520 (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://cveledger.app/cve/CVE-2026-13253)Record last updated .