CVE-2026-6427 (GCVE-0-2026-6427)
Vulnerability from cvelistv5 – Published: 2026-05-28 06:45 – Updated: 2026-05-28 10:34
VLAI
Title
a3 Lazy Load <= 2.7.6 - Authenticated (Contributor+) Stored Cross-Site Scripting via Video Element
Summary
The a3 Lazy Load plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 2.7.6 This is due to a regex bug in the _filter_videos() method that breaks HTML attribute quoting when processing crafted <video> elements, combined with unescaped output in the admin/views/form-data.php template. An authenticated attacker with Contributor-level access can insert a crafted <video> tag whose src attribute contains an embedded class=" substring that tricks the plugin's class-replacement regex into consuming an attribute-value closing quote. This shifts the HTML5 parser's quote boundary, promoting attacker-controlled text from inside a quoted attribute value into standalone event-handler attributes (autofocus, onfocus). The injected script executes in the browser of any user (including administrators) who views the post.
Severity
6.4 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
8 references
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| a3rev | a3 Lazy Load |
Affected:
0 , ≤ 2.7.6
(semver)
|
Credits
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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