Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-45372— cpp-httplib: HTTP header value percent-decoding in server-side `parse_header` enables CRLF injection

Quick assessment

Affected
yhirose cpp-httplib
Exploitation
Public or AI PoC available; prioritize validation
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

cpp-httplib是yhirose个人开发者的一款使用C++语言编写的HTTP/HTTPS服务器和客户端库。 cpp-httplib 0.44.0之前版本存在环境问题漏洞，该漏洞源于服务器解析请求时对除Location和Referer外的每个标头值应用百分号解码，有效性检查在解码前运行，导致编码的%0D%0A通过检查并扩展为字面 字节对。

CVSS 9.9 · Critical EPSS 0.41% · P33

Affected Version Matrix 1

VendorProduct Version RangeStatus
yhirose cpp-httplib < 0.44.0 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-45372

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
cpp-httplib: HTTP header value percent-decoding in server-side `parse_header` enables CRLF injection
Source: CVE Program / CVE List V5
Vulnerability Description
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.44.0, when cpp-httplib's server parses an incoming request, it applies percent-decoding to every header value except Location and Referer. The validity check (is_field_value) is run before decoding, so encoded %0D%0A passes the check and is then expanded to a literal \r\n byte pair inside the stored header value. This vulnerability is fixed in 0.44.0.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L
Source: CVE Program / CVE List V5
Vulnerability Type
对CRLF序列的转义处理不恰当(CRLF注入)
Source: CVE Program / CVE List V5
Vulnerability Title
cpp-httplib 环境问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
cpp-httplib是yhirose个人开发者的一款使用C++语言编写的HTTP/HTTPS服务器和客户端库。 cpp-httplib 0.44.0之前版本存在环境问题漏洞，该漏洞源于服务器解析请求时对除Location和Referer外的每个标头值应用百分号解码，有效性检查在解码前运行，导致编码的%0D%0A通过检查并扩展为字面 字节对。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
yhirose cpp-httplib < 0.44.0 -

II. Public POCs for CVE-2026-45372

# POC Description Source Link Shenlong Link
AI-Generated POC Premium
Qwen3.6-35B-A3B · 8103 chars
Pro+ exclusive includes:
Vulnerability reproduction recording (real sandbox build + trigger, exclusive)
In-depth vulnerability mechanism
Trigger conditions & impact
Full executable POC code
Exploit chain & mitigation
POC zip download
100+ AI POC generations per month

III. Intelligence Information for CVE-2026-45372

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-45372 (1)

Same Patch Batch · yhirose · 2026-05-29 · 3 CVEs total

CVE-2026-45352 5.3 MEDIUM cpp-httplib DoS: Negative chunk-size in chunked Transfer-Encoding
CVE-2026-46527 cpp-httplib: Malicious `X-Forwarded-For` Under Trusted-Proxy Configuration Triggers Empty

IV. Related Vulnerabilities

Same product: cpp-httplib
Same vendor: yhirose
Same weakness: CWE-93

V. Comments for CVE-2026-45372

No comments yet

Leave a comment