{"id":"CVE-2025-46728","state":"PUBLISHED","title":"cpp-httplib has Unbounded Memory Allocation in Chunked/No-Length Requests","description":"cpp-httplib is a C++ header-only HTTP/HTTPS server and client library. Prior to version 0.20.1, the library fails to enforce configured size limits on incoming request bodies when `Transfer-Encoding: chunked` is used or when no `Content-Length` header is provided. A remote attacker can send a chunked request without the terminating zero-length chunk, causing uncontrolled memory allocation on the server. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.20.1 fixes the issue by enforcing limits during parsing. If the limit is exceeded at any point during reading, the connection is terminated immediately. A short-term workaround through a Reverse Proxy is available. If updating the library immediately is not feasible, deploy a reverse proxy (e.g., Nginx, HAProxy) in front of the `cpp-httplib` application. Configure the proxy to enforce maximum request body size limits, thereby stopping excessively large requests before they reach the vulnerable library code.","publishedAt":"2025-05-06T00:45:25.130Z","updatedAt":"2025-05-06T02:43:44.757Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["yhirose cpp-httplib"],"affected":[{"vendor":"yhirose","product":"cpp-httplib","versions":[{"version":"< 0.20.1","status":"affected"}]}],"references":["https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-px83-72rx-v57c","https://github.com/yhirose/cpp-httplib/commit/7b752106ac42bd5b907793950d9125a0972c8e8e"],"weaknesses":["CWE-400"],"ingestedAt":"2026-10-29T20:09:17.366Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/46xxx/CVE-2025-46728.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2025-46728","state":"PUBLISHED","datePublished":"2025-05-06T00:45:25.130Z","dateUpdated":"2025-05-06T02:43:44.757Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2025-04-28T20:56:09.084Z"},"containers":{"cna":{"title":"cpp-httplib has Unbounded Memory Allocation in Chunked/No-Length Requests","descriptions":[{"lang":"en","value":"cpp-httplib is a C++ header-only HTTP/HTTPS server and client library. Prior to version 0.20.1, the library fails to enforce configured size limits on incoming request bodies when `Transfer-Encoding: chunked` is used or when no `Content-Length` header is provided. A remote attacker can send a chunked request without the terminating zero-length chunk, causing uncontrolled memory allocation on the server. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.20.1 fixes the issue by enforcing limits during parsing. If the limit is exceeded at any point during reading, the connection is terminated immediately. A short-term workaround through a Reverse Proxy is available. If updating the library immediately is not feasible, deploy a reverse proxy (e.g., Nginx, HAProxy) in front of the `cpp-httplib` application. Configure the proxy to enforce maximum request body size limits, thereby stopping excessively large requests before they reach the vulnerable library code."}],"affected":[{"vendor":"yhirose","product":"cpp-httplib","versions":[{"version":"< 0.20.1","status":"affected"}]}],"references":[{"url":"https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-px83-72rx-v57c","name":"https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-px83-72rx-v57c","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/yhirose/cpp-httplib/commit/7b752106ac42bd5b907793950d9125a0972c8e8e","name":"https://github.com/yhirose/cpp-httplib/commit/7b752106ac42bd5b907793950d9125a0972c8e8e","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","lang":"en","description":"CWE-400: Uncontrolled Resource Consumption","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2025-05-06T00:45:25.130Z"},"source":{"advisory":"GHSA-px83-72rx-v57c","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2025-05-06T02:43:34.093374Z","id":"CVE-2025-46728","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-05-06T02:43:44.757Z"}}]}}}