What’s Vulnerable › Vulnerabilities

CVE-2023-40518

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-08-14 · updated 2026-06-17

Description

LiteSpeed OpenLiteSpeed before 1.7.18 does not strictly validate HTTP request headers.

Affected products

• LiteSpeed Technologies OpenLiteSpeed: before 1.7.18 — fixed in 1.7.18

How to fix

Upgrade to a fixed version: LiteSpeed Technologies OpenLiteSpeed 1.7.18. Check the vendor advisory for mitigations.

References

• https://openlitespeed.org/release-log/version-1-7-x/
• https://www.litespeedtech.com/products/litespeed-web-server/release-log
• https://openlitespeed.org/release-log/version-1-7-x/
• https://www.litespeedtech.com/products/litespeed-web-server/release-log

Get alerted when CVE-2023-40518 or the next vulnerability affects your stack