Affected: curl

When an FTP wildcard `LIST` operation fails, libcurl omits the restoration path meant for successful listings, leaving the write callback set to the internal listing parser and the write callback data pointing directly to the easy handle. Subsequent reuse of this handle triggers an immediate crash, and cloning it via `curl_easy_duphandle()` copies this corrupted state into the duplicate. If the original handle is subsequently freed, executing a transfer on the cloned handle causes a heap use-after-free read against the dangling handle reference; alternatively, reusing the original or cloned handle while changing only `CURLOPT_WRITEDATA` (and omitting `CURLOPT_WRITEFUNCTION`) results in type confusion, forcing the internal parser to interpret incoming server response bytes into memory at the application-supplied write data pointer.

Affected: Ubuntu:26.04:LTS: curl

It was discovered that curl, when built with GnuTLS support, had an out-of-bounds read in the WebSocket send path. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-107928)

Maksim discovered that curl did not correctly include the interface binding in connection reuse decisions when CURLOPT_INTERFACE was used. An attacker could possibly use this issue to cause connections to go out from an unintended source address. (CVE-2026-107929)

Stanislav Fort discovered that curl did not properly clear AWS SigV4 authentication state when CURLOPT_AWS_SIGV4 was set to NULL. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-86409)

Stanislav Fort discovered that the curl command line tool did not set SSH host verification options when following redirects to SFTP or SCP URLs. An attacker could possibly use this issue to perform machine-in-the-middle attacks. (CVE-2026-86410)

Stanislav Fort discovered that curl did not properly handle cookie jar entries that could not be reloaded. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-86412)

Stanislav Fort discovered that an HTTP proxy could trick libcurl into sending credentials to the proxy itself by responding to a CONNECT request with an unexpected authentication challenge. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-86414)

Stanislav Fort discovered that curl did not correctly handle HSTS entries…