CVE-2025-46728

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.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-400"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46728.json"
}

References

Affected packages

Git / github.com/yhirose/cpp-httplib

Affected ranges

Type

GIT

Repo

https://github.com/yhirose/cpp-httplib

Events

Introduced

Fixed

3af7f2c16147f3fbc6e4d717032daf505dc1652c

Fixed

7b752106ac42bd5b907793950d9125a0972c8e8e

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "0.20.1"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ],
    "cpe": "cpe:2.3:a:cpp-httplib_project:cpp-httplib:*:*:*:*:*:*:*:*"
}

Affected versions

v0.*

v0.10.0

v0.10.1

v0.10.2

v0.10.3

v0.10.4

v0.10.5

v0.10.6

v0.10.7

v0.10.8

v0.10.9

v0.11.0

v0.11.1

v0.11.2

v0.11.3

v0.11.4

v0.12.0

v0.12.1

v0.12.2

v0.12.3

v0.12.4

v0.12.5

v0.12.6

v0.13.0

v0.13.1

v0.13.2

v0.13.3

v0.14.0

v0.14.1

v0.14.2

v0.14.3

v0.15.0

v0.15.1

v0.15.2

v0.15.3

v0.16.0

v0.16.1

v0.16.2

v0.16.3

v0.17.0

v0.17.1

v0.17.2

v0.17.3

v0.18.0

v0.18.1

v0.18.2

v0.18.3

v0.18.4

v0.18.5

v0.18.6

v0.18.7

v0.19.0

v0.2.0

v0.2.1

v0.2.2

v0.2.3

v0.2.4

v0.2.5

v0.2.6

v0.20.0

v0.3.0

v0.3.1

v0.3.2

v0.3.3

v0.4.0

v0.4.1

v0.4.2

v0.5.0

v0.5.1

v0.5.10

v0.5.11

v0.5.12

v0.5.13

v0.5.2

v0.5.3

v0.5.4

v0.5.5

v0.5.6

v0.5.7

v0.5.8

v0.5.9

v0.6.0

v0.6.1

v0.6.2

v0.6.3

v0.6.4

v0.6.5

v0.6.6

v0.6.7

v0.7.0

v0.7.1

v0.7.10

v0.7.11

v0.7.12

v0.7.13

v0.7.14

v0.7.15

v0.7.16

v0.7.17

v0.7.18

v0.7.2

v0.7.3

v0.7.4

v0.7.5

v0.7.6

v0.7.7

v0.7.8

v0.7.9

v0.8.0

v0.8.1

v0.8.2

v0.8.3

v0.8.4

v0.8.5

v0.8.6

v0.8.7

v0.8.8

v0.8.9

v0.9.0

v0.9.1

v0.9.10

v0.9.2

v0.9.3

v0.9.4

v0.9.5

v0.9.6

v0.9.7

v0.9.8

v0.9.9

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-46728.json"

vanir_signatures

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        "id": "CVE-2025-46728-18f6418d",
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        },
        "signature_type": "Function"
    },
    {
        "target": {
            "file": "test/test.cc"
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vanir_signatures_modified

"2026-08-12T15:16:32Z"