Vulnerability · Published Apr 6, 2026 · Assigned by GitHub_M

CVE-2026-33752Redirect-based SSRF leading to internal network access in curl_cffi (with TLS impersonation bypass)

High 8.6

In plain English

A high-severity server-side request forgery in curl_cffi from lexiforest. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.6High

Exploit odds (30 days)0.5%top 58.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack tooling1Public PoC

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	curl-cffi	0.15.0	GHSA-qw2m-4pqf-rmpp
PyPI	curl-cffi	0.15.0	PYSEC-2026-2431

Affected products (as reported)

Vendor	Product	Versions
lexiforest	curl_cffi	< 0.15.0

Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

References

https://github.com/lexiforest/curl_cffi/security/advisories/GHSA-qw2m-4pqf-rmpp x_refsource_CONFIRM