CVE-2026-33752

HIGH

Redirect-based SSRF leading to internal network access in curl_cffi (with TLS impersonation bypass)

Title source: cna
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-33752. PoCs published by redyank.

AI-analyzed exploit summary The repository provides a detailed technical analysis of CVE-2026-33752, a redirect-based SSRF vulnerability in curl_cffi. It explains how the library's lack of internal IP range validation and automatic redirect following can lead to unauthorized access to internal services, including cloud metadata endpoints.

Description

curl_cffi is the a Python binding for curl. Prior to 0.15.0, curl_cffi does not restrict requests to internal IP ranges, and follows redirects automatically via the underlying libcurl. Because of this, an attacker-controlled URL can redirect requests to internal services such as cloud metadata endpoints. In addition, curl_cffi’s TLS impersonation feature can make these requests appear as legitimate browser traffic, which may bypass certain network controls. This vulnerability is fixed in 0.15.0.

Exploits (1)

nomisec WRITEUP
by redyank · poc
https://github.com/redyank/CVE-2026-33752

The repository provides a detailed technical analysis of CVE-2026-33752, a redirect-based SSRF vulnerability in curl_cffi. It explains how the library's lack of internal IP range validation and automatic redirect following can lead to unauthorized access to internal services, including cloud metadata endpoints.

Classification
Writeup 95%
Attack Type
Ssrf
Complexity
Moderate
Reliability
Reliable
Target: curl_cffi
No auth needed
Prerequisites: ability to control a URL that the target application will request · network access to the target application
devstral-2 · analyzed Apr 28, 2026 Full analysis →

References (1)

Core 1
Core References

Scores

CVSS v3 8.6
EPSS 0.0046
EPSS Percentile 36.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-918
Status published
Products (3)
lexiforest/curl_cffi 0.15.0 beta1 (4 CPE variants)
lexiforest/curl_cffi < 0.15.0 (2 CPE variants)
pypi/curl_cffi 0 - 0.15.0PyPI
Published Apr 06, 2026
Tracked Since Apr 06, 2026