Vulnerability record · CVE-2022-42915 · published 29 October 2022
CVE-2022-42915: Haxx curl double free vulnerability
Haxx · Curl
curl before 7.86.0 has a double free. If curl is told to use an HTTP proxy for a transfer with a non-HTTP(S) URL, it sets up the connection to the remote server by issuing a CONNECT request to the proxy, and then tunnels the rest of the protocol through. An HTTP proxy might refuse this request (HTTP proxies often only allow outgoing connections to specific port numbers, like 443 for HTTPS) and instead return a non-200 status code to the client. Due to flaws in the error/cleanup handling, this could trigger a double free in curl if one of the following schemes were used in the URL for the transfer: dict, gopher, gophers, ldap, ldaps, rtmp, rtmps, or telnet. The earliest affected version is 7.77.0.
Description
curl before 7.86.0 has a double free. If curl is told to use an HTTP proxy for a transfer with a non-HTTP(S) URL, it sets up the connection to the remote server by issuing a CONNECT request to the proxy, and then tunnels the rest of the protocol through. An HTTP proxy might refuse this request (HTTP proxies often only allow outgoing connections to specific port numbers, like 443 for HTTPS) and instead return a non-200 status code to the client. Due to flaws in the error/cleanup handling, this could trigger a double free in curl if one of the following schemes were used in the URL for the transfer: dict, gopher, gophers, ldap, ldaps, rtmp, rtmps, or telnet. The earliest affected version is 7.77.0.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
9 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
Track CVE-2022-42915 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2022-42915), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.
