High severity · published Aug 14, 2023
CVE-2023-40518
LiteSpeed OpenLiteSpeed before 1.7.18 does not strictly validate HTTP request headers
7.5
CVSS
0.7%
EPSS
No
On KEV
Description
LiteSpeed OpenLiteSpeed before 1.7.18 does not strictly validate HTTP request headers.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
Openlitespeed · Litespeedtech
before 1.7.18 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-40518
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-40518
Release Notes
https://openlitespeed.org/release-log/version-1-7-x/
Release Notes
https://www.litespeedtech.com/products/litespeed-web-server/release-log
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