Redirect-based SSRF leading to internal network access in curl_cffi (with TLS impersonation bypass)
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-33752
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 13:13 UTC · Revision 1
Source evidence
Redirect-based SSRF leading to internal network access in curl_cffi (with TLS impersonation bypass)
core-osv · Original sourcePublished 6 Apr 2026, 15:01 UTC
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.
osv:CVE-2026-33752
Complete source record
{
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"url": "https://osv.dev/vulnerability/CVE-2026-33752",
"method": "structured",
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"title": "Redirect-based SSRF leading to internal network access in curl_cffi (with TLS impersonation bypass)",
"summary": "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.",
"evidence": "osv:CVE-2026-33752",
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"PYSEC-2026-2431"
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"affected": [
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"type": "GIT",
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"database_specific": {
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}
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],
"modified": "2026-10-28T02:30:28.846394989Z",
"provider": "osv",
"references": [
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"https://github.com/lexiforest/curl_cffi/security/advisories/GHSA-qw2m-4pqf-rmpp",
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"provider_metadata": {
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"cna_assigner": "GitHub_M",
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"related_cves": [
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"evidence": "/id"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 495727,
"published_at": "2026-04-06T15:01:44.844+00:00"
}