CVE-2025-52887
cpp-httplib has unlimited number of http header fields, which causes memory leak
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
cpp-httplib has unlimited number of http header fields, which causes memory leak
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
- Record
CVE-2025-52887- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
EUVDEUVD-2025-19196
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
- Record
EUVD-2025-19196- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
NVD
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
- Record
CVE-2025-52887- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSV
cpp-httplib has unlimited number of http header fields, which causes memory leak
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
- Record
CVE-2025-52887- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVOESA-2025-1721
cpp-httplib security update
A C++11 single-file header-only cross platform HTTP/HTTPS library. It's extremely easy to setup. Just include httplib.h file in your code!
Security Fix(es):
cpp-httplib is an HTTP/HTTPS server and client library written in C++ by individual developers of yhirose. cpp-httplib version 0.21.0 has a resource management error vulnerability, which originated from the unlimited number of HTTP headers, which may cause the system to run out of memory.(CVE-2025-52887)
- Record
OESA-2025-1721- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVOESA-2025-1722
cpp-httplib security update
A C++11 single-file header-only cross platform HTTP/HTTPS library. It's extremely easy to setup. Just include httplib.h file in your code!
Security Fix(es):
cpp-httplib is an HTTP/HTTPS server and client library written in C++ by individual developers of yhirose. cpp-httplib version 0.21.0 has a resource management error vulnerability, which originated from the unlimited number of HTTP headers, which may cause the system to run out of memory.(CVE-2025-52887)
- Record
OESA-2025-1722- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Show 4 moreShow less
OSVOESA-2025-1723
cpp-httplib security update
A C++11 single-file header-only cross platform HTTP/HTTPS library. It's extremely easy to setup. Just include httplib.h file in your code!
Security Fix(es):
cpp-httplib is an HTTP/HTTPS server and client library written in C++ by individual developers of yhirose. cpp-httplib version 0.21.0 has a resource management error vulnerability, which originated from the unlimited number of HTTP headers, which may cause the system to run out of memory.(CVE-2025-52887)
- Record
OESA-2025-1723- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVOESA-2025-1724
cpp-httplib security update
A C++11 single-file header-only cross platform HTTP/HTTPS library. It's extremely easy to setup. Just include httplib.h file in your code!
Security Fix(es):
cpp-httplib is an HTTP/HTTPS server and client library written in C++ by individual developers of yhirose. cpp-httplib version 0.21.0 has a resource management error vulnerability, which originated from the unlimited number of HTTP headers, which may cause the system to run out of memory.(CVE-2025-52887)
- Record
OESA-2025-1724- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVOESA-2025-1829
cpp-httplib security update
A C++11 single-file header-only cross platform HTTP/HTTPS library. It's extremely easy to setup. Just include httplib.h file in your code!
Security Fix(es):
cpp-httplib is an HTTP/HTTPS server and client library written in C++ by individual developers of yhirose. cpp-httplib version 0.21.0 has a resource management error vulnerability, which originated from the unlimited number of HTTP headers, which may cause the system to run out of memory.(CVE-2025-52887)
- Record
OESA-2025-1829- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2025-52887
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
- Record
UBUNTU-CVE-2025-52887- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
cpp-httplibopenEuler:22.03-LTS-SP3 |
before 0.22.0-1.oe2203sp3 | 0.22.0-1.oe2203sp3 |
cpp-httplibopenEuler:22.03-LTS-SP4 |
before 0.22.0-1.oe2203sp4 | 0.22.0-1.oe2203sp4 |
cpp-httplibopenEuler:24.03-LTS |
before 0.22.0-1.oe2403 | 0.22.0-1.oe2403 |
cpp-httplibopenEuler:24.03-LTS-SP1 |
before 0.22.0-1.oe2403sp1 | 0.22.0-1.oe2403sp1 |
cpp-httplibopenEuler:24.03-LTS-SP2 |
before 0.22.0-1.oe2403sp2 | 0.22.0-1.oe2403sp2 |
cpp-httplibUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 0.9.9+ds-10.9.10+ds-10.10.1+ds-10.10.2+ds-10.10.3+ds-10.10.3+ds-1ubuntu0.1~esm10.10.3+ds-1ubuntu0.1~esm2 |
None known |
cpp-httplibUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 0.13.1+ds-1ubuntu10.14.3+ds-10.14.3+ds-1.10.14.3+ds-1.1build10.14.3+ds-1.1build20.14.3+ds-1.1ubuntu0.1~esm10.14.3+ds-1.1ubuntu0.1~esm2 |
None known |
cpp-httplibUbuntu:25.10 |
All versions, plus listed versions 0.18.7-10.18.7-1ubuntu0.25.10.10.18.7-1ubuntu0.25.10.2 |
None known |
cpp-httplibUbuntu:Pro:26.04:LTS |
All versions, plus listed versions 0.18.7-10.26.0+ds-2ubuntu20.26.0+ds-2ubuntu30.26.0+ds-2ubuntu3+esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-52887 is a high vulnerability (CVSS 7.5) in Yhirose Cpp-httplib, published June 26, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.49%, the 42nd percentile. Fixed in cpp-httplib 0.22.0-1.oe2203sp3.
References
github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjhg-gf59-p92h
nvd.nist.gov/vuln/detail/CVE-2025-52887
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2025-1721
Show 5 moreShow less
ubuntu.com/security/CVE-2025-52887
cve.org/CVERecord?id=CVE-2025-52887