High severity · published Jul 10, 2025
CVE-2025-53628
cpp-httplib does not limit the length of a line
8.8
CVSS
0.5%
EPSS
No
On KEV
Description
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.20.1, cpp-httplib does not have a limit for a unique line, permitting an attacker to explore this to allocate memory arbitrarily. This vulnerability is fixed in 0.20.1. NOTE: This vulnerability is related to CVE-2025-53629.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CP
cpp-httplib · yhirose
< 0.20.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-53628
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-53628
Patch
https://github.com/yhirose/cpp-httplib/commit/7b752106ac42bd5b907793950d9125a0972c8e8e
Exploit
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-j6p8-779x-p5pw
Not Applicable
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-qjmq-h3cc-qv6w
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