CVE-2026-3784

curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a server, even if the new request uses different credentials for the HTTP proxy. The proper behavior is to create or use a separate connection.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-3784.html	Patch Vendor Advisory
https://curl.se/docs/CVE-2026-3784.json	Vendor Advisory
https://hackerone.com/reports/3584903	Exploit Issue Tracking Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/03/11/3	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-11 11:16

Updated : 2026-03-12 14:09

NVD link : CVE-2026-3784

Mitre link : CVE-2026-3784

CVE.ORG link : CVE-2026-3784

JSON object : View

Products Affected

haxx

curl

CWE

CWE-305

Authentication Bypass by Primary Weakness

{"id": "CVE-2026-3784", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 3.9}]}, "published": "2026-03-11T11:16:00.437", "references": [{"url": "https://curl.se/docs/CVE-2026-3784.html", "tags": ["Patch", "Vendor Advisory"], "source": "2499f714-1537-4658-8207-48ae4bb9eae9"}, {"url": "https://curl.se/docs/CVE-2026-3784.json", "tags": ["Vendor Advisory"], "source": "2499f714-1537-4658-8207-48ae4bb9eae9"}, {"url": "https://hackerone.com/reports/3584903", "tags": ["Exploit", "Issue Tracking", "Third Party Advisory"], "source": "2499f714-1537-4658-8207-48ae4bb9eae9"}, {"url": "http://www.openwall.com/lists/oss-security/2026/03/11/3", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-305"}]}], "descriptions": [{"lang": "en", "value": "curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a\nserver, even if the new request uses different credentials for the HTTP proxy.\nThe proper behavior is to create or use a separate connection."}, {"lang": "es", "value": "curl reutilizar\u00eda err\u00f3neamente una conexi\u00f3n proxy HTTP existente haciendo CONNECT a un servidor, incluso si la nueva solicitud utiliza credenciales diferentes para el proxy HTTP. El comportamiento adecuado es crear o usar una conexi\u00f3n separada."}], "lastModified": "2026-03-12T14:09:50.470", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "94E54714-769C-4910-9044-7BFF8F9F94F0", "versionEndExcluding": "8.18.0", "versionStartIncluding": "7.7"}], "operator": "OR"}]}], "sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9"}