yhirose

13 exploits Active since Apr 2021
CVE-2026-29076 WRITEUP MEDIUM WRITEUP
cpp-httplib < 0.37.0 - Denial of Service via RFC 5987 Filename Regex Backtracking
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.37.0, cpp-httplib uses std::regex (libstdc++) to parse RFC 5987 encoded filename* values in multipart Content-Disposition headers. The regex engine in libstdc++ implements backtracking via deep recursion, consuming one stack frame per input character. An attacker can send a single HTTP POST request with a crafted filename* parameter that causes uncontrolled stack growth, resulting in a stack overflow (SIGSEGV) that crashes the server process. This issue has been patched in version 0.37.0.
CVSS 5.9
CVE-2026-28434 WRITEUP MEDIUM WRITEUP
cpp-httplib <0.35.0 - Info Disclosure
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, when a request handler throws a C++ exception and the application has not registered a custom exception handler via set_exception_handler(), the library catches the exception and writes its message directly into the HTTP response as a header named EXCEPTION_WHAT. This header is sent to whoever made the request, with no authentication check and no special configuration required to trigger it. The behavior is on by default. A developer who does not know to opt in to set_exception_handler() will ship a server that leaks internal exception messages to any client. This vulnerability is fixed in 0.35.0.
CVSS 5.3
CVE-2026-28435 WRITEUP HIGH WRITEUP
cpp-httplib < 0.35.0 - Uncontrolled Resource Consumption via Decompressed Request Body Bypass
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, cpp-httplib (httplib.h) does not enforce Server::set_payload_max_length() on the decompressed request body when using HandlerWithContentReader (streaming ContentReader) with Content-Encoding: gzip (or other supported encodings). A small compressed payload can expand beyond the configured payload limit and be processed by the application, enabling a payload size limit bypass and potential denial of service (CPU/memory exhaustion). This vulnerability is fixed in 0.35.0.
CVSS 7.5
CVE-2020-23914 WRITEUP MEDIUM WRITEUP
cpp-peglib < 0.1.12 - Denial of Service via NULL Pointer Dereference in peg::AstOptimizer::optimize()
An issue was discovered in cpp-peglib through v0.1.12. A NULL pointer dereference exists in the peg::AstOptimizer::optimize() located in peglib.h. It allows an attacker to cause Denial of Service.
CVSS 5.5
CVE-2020-23915 WRITEUP MEDIUM WRITEUP
cpp-peglib <v0.1.12 - Buffer Overflow
An issue was discovered in cpp-peglib through v0.1.12. peg::resolve_escape_sequence() in peglib.h has a heap-based buffer over-read.
CVSS 5.5
CVE-2023-26130 WRITEUP HIGH WRITEUP
yhirose/cpp-httplib < 0.12.4 - CRLF Injection
Versions of the package yhirose/cpp-httplib before 0.12.4 are vulnerable to CRLF Injection when untrusted user input is used to set the content-type header in the HTTP .Patch, .Post, .Put and .Delete requests. This can lead to logical errors and other misbehaviors. **Note:** This issue is present due to an incomplete fix for [CVE-2020-11709](https://security.snyk.io/vuln/SNYK-UNMANAGED-YHIROSECPPHTTPLIB-2366507).
CVSS 7.5
CVE-2025-0825 WRITEUP MEDIUM WRITEUP
cpp-httplib 0.17.3-0.18.3 - HTTP Response Splitting via Null Byte Prefixed CRLF Injection
cpp-httplib version v0.17.3 through v0.18.3 fails to filter CRLF characters ("\r\n") when those are prefixed with a null byte. This enables attackers to exploit CRLF injection that could further lead to HTTP Response Splitting, XSS, and more.
CVSS 5.3
CVE-2025-52887 WRITEUP HIGH WRITEUP
cpp-httplib 0.21.0 - Uncontrolled Resource Consumption via HTTP Header Processing
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.
CVSS 7.5
CVE-2025-53629 WRITEUP HIGH WRITEUP
cpp-httplib <0.23.0 - Memory Corruption
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.23.0, incoming requests using Transfer-Encoding: chunked in the header can allocate memory arbitrarily in the server, potentially leading to its exhaustion. This vulnerability is fixed in 0.23.0. NOTE: This vulnerability is related to CVE-2025-53628.
CVSS 7.5
CVE-2025-66570 WRITEUP CRITICAL WRITEUP
cpp-httplib <0.27.0 - Info Disclosure
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability allows attacker-controlled HTTP headers to influence server-visible metadata, logging, and authorization decisions. An attacker can inject headers named REMOTE_ADDR, REMOTE_PORT, LOCAL_ADDR, LOCAL_PORT that are parsed into the request header multimap via read_headers() in httplib.h (headers.emplace), then the server later appends its own internal metadata using the same header names in Server::process_request without erasing duplicates. Because Request::get_header_value returns the first entry for a header key (id == 0) and the client-supplied headers are parsed before server-inserted headers, downstream code that uses these header names may inadvertently use attacker-controlled values. Affected files/locations: cpp-httplib/httplib.h (read_headers, Server::process_request, Request::get_header_value, get_header_value_u64) and cpp-httplib/docker/main.cc (get_client_ip, nginx_access_logger, nginx_error_logger). Attack surface: attacker-controlled HTTP headers in incoming requests flow into the Request.headers multimap and into logging code that reads forwarded headers, enabling IP spoofing, log poisoning, and authorization bypass via header shadowing. This vulnerability is fixed in 0.27.0.
CVSS 10.0
CVE-2025-66577 WRITEUP MEDIUM WRITEUP
cpp-httplib <0.27.0 - Log Poisoning
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability allows attacker-controlled HTTP headers to influence server-visible metadata, logging, and authorization decisions. An attacker can supply X-Forwarded-For or X-Real-IP headers which get accepted unconditionally by get_client_ip() in docker/main.cc, causing access and error logs (nginx_access_logger / nginx_error_logger) to record spoofed client IPs (log poisoning / audit evasion). This vulnerability is fixed in 0.27.0.
CVSS 5.3
CVE-2026-21428 WRITEUP HIGH WRITEUP
cpp-httplib < 0.30.0 - CRLF Injection via User-Supplied Headers
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR & LF characters in user supplied headers, allowing untrusted header value to escape header lines. This vulnerability allows attackers to add extra headers, modify request body unexpectedly & trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue.
CVSS 7.5
CVE-2026-22776 WRITEUP HIGH WRITEUP
cpp-httplib < 0.30.1 - Denial of Service via Unbounded Decompression of HTTP Request Bodies
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.1, a Denial of Service (DoS) vulnerability exists in cpp-httplib due to the unsafe handling of compressed HTTP request bodies (Content-Encoding: gzip, br, etc.). The library validates the payload_max_length against the compressed data size received from the network, but does not limit the size of the decompressed data stored in memory.
CVSS 7.5