LiteSpeed Cache <= 7.8.1 - Unauthenticated Stored Cross-Site Scripting via Comment Content
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 7.8.1 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. A comment payload crafted exclusively from decimal numeric character references (e.g. ", <, >) placed inside an allowed element such as <code> bypasses WordPress's wp_kses sanitization, as kses does not treat a data-settings="..." substring within text content as an HTML attribute, allowing the malicious payload to reach the vulnerable function. For this to be exploitable, the site must allow users with previously approved comments to write new comments, and the require_name_email setting must be disabled.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| litespeedtech | LiteSpeed Cache | up to 7.8.1 | — | No fix listed | CNA |
- LiteSpeed Cache Vendorlitespeedtech Affected up to 7.8.1 Fixed in — No fix listed CNA
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:litespeedtech:litespeed_cache:*:*:*:*:*:*:*:* | — | — | litespeedtech |
- cpe:2.3:a:litespeedtech:litespeed_cache:*:*:*:*:*:*:*:* Versions — — ·litespeedtech
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-18978
- 2026-10-03 Alias added: GHSA-rm48-v2jm-fxxq
References
Other 7
- https://www.wordfence.com/threat-intel/vulnerabilities/id/0b045f3d-8412-4e35-b369-2b485639274d?source=cve
- https://plugins.trac.wordpress.org/browser/litespeed-cache/trunk/src/media.cls.php#L1405
- https://plugins.trac.wordpress.org/browser/litespeed-cache/trunk/src/media.cls.php#L1358
- https://plugins.trac.wordpress.org/browser/litespeed-cache/trunk/src/media.cls.php#L1317
- https://plugins.trac.wordpress.org/browser/litespeed-cache/trunk/src/media.cls.php#L777
- https://plugins.trac.wordpress.org/changeset/3635849/litespeed-cache/trunk/src/media.cls.php
- https://plugins.trac.wordpress.org/changeset?old_path=%2Flitespeed-cache/tags/7.8.1&new_path=%2Flitespeed-cache/tags/7.9
More litespeedtech vulnerabilities
- TI-2026-35606 LiteSpeed User-End cPanel Plugin before 2.4.5 allows privilege escalation (possibly to… KEVCVSS 4.0CRITICAL 10.0
- TI-2026-39296 LiteSpeed cPanel plugin before 2.4.8 (as distributed in LiteSpeed WHM PlugIn before… KEVCVSS 3.1HIGH 8.5
- TI-2024-29589 WordPress LiteSpeed Cache plugin < 6.5.0.1 - Unauthenticated Account Takeover via Cookie Leak vulnerability CVSS 3.1CRITICAL 9.8
- TI-2024-18601 WordPress LiteSpeed Cache plugin <= 6.3.0.1 - Unauthenticated Privilege Escalation vulnerability CVSS 3.1CRITICAL 9.8
- TI-2022-00030 Authenticated Remote Code Execution in OpenLiteSpeed Web Server CVSS 3.1HIGH 8.8
- TI-2026-83023 Client certificate bypass over HTTP/3 in OpenLiteSpeed CVSS 4.0HIGH 8.2
Sources
- CVE-2026-18978 · CVE Program
- CVE-2026-18978 · NVD
- FIRST EPSS
- GHSA-rm48-v2jm-fxxq · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences