USN-8932-1: curl vulnerabilities
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. This
issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS.
(CVE-2026-86409)
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 when an includeSubDomains parent entry was imported before a
longer-lived child entry. An attacker could possibly use this issue to
cause curl to use unencrypted HTTP connections. This issue only affected
Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-87862)
Stanislav Fort discovered that curl did not properly handle HSTS max-age
values that exceeded calendar time structure bounds. An attacker could
possibly use this issue to cause a denial of service or data loss. This
issue only affected Ubuntu 24.04 LTS. (CVE-2026-87863)
Stanislav Fort discovered that curl did not properly handle IMAP APPEND
commands when CURLOPT_CRLF was enabled, allowing overflow bytes to be
interpreted as pipelined commands. An authenticated attacker could
possibly use this issue to inject arbitrary IMAP commands.
(CVE-2026-87864)
Joshua Rogers discovered that libcurl had a use-after-free vulnerability
in the FTP wildcard matching code. An attacker could possibly use this
issue to cause curl to crash, resulting in a denial of service, or
execute arbitrary code. (CVE-2026-92388)
Joshua Rogers discovered that libcurl's TFTP state machine did not
properly validate transfer directions, allowing a malicious server to
force the client into transmit mode. An attacker could possibly use this
issue to obtain sensitive information. (CVE-2026-92389)
Joshua Rogers discovered that curl had a stack overflow vulnerability
when processing deeply nested MIME structures. An attacker could
possibly use this issue to cause curl to crash, resulting in a denial of
service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS,
Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-92391)
Joshua Rogers discovered that libcurl could expose credentials in the
URL returned by CURLINFO_EFFECTIVE_URL when credentials were retrieved
from a .netrc file. An attacker could possibly use this issue to obtain
sensitive information. This issue only affected Ubuntu 20.04 LTS, Ubuntu
22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-94266)