Packages
- curl - HTTP, HTTPS, and FTP client and client libraries
Details
Zhicheng Chen discovered that curl could incorrectly reuse the wrong
connection for Negotiate-authenticated HTTP or HTTPS requests. This could
result in the use of credentials from a different connection, contrary to
expectations. This issue only affected Ubuntu 20.04 LTS. (CVE-2026-1965)
It was discovered that curl incorrectly leaked OAuth2 bearer tokens when
following a redirect. This could result in tokens being sent to the wrong
host, contrary to expectations. This issue only affected Ubuntu 20.04 LTS.
(CVE-2026-3783)
Muhamad Arga Reksapati discovered that curl incorrectly reused existing
HTTP proxy connections even if the request used different credentials. This
could result in the use of incorrect credentials, contrary to expectations.
(CVE-2026-3784)
Zhicheng Chen discovered that curl could incorrectly reuse the wrong
connection for Negotiate-authenticated HTTP or HTTPS requests. This could
result in the use of credentials from a different connection, contrary to
expectations. This issue only affected Ubuntu 20.04 LTS. (CVE-2026-1965)
It was discovered that curl incorrectly leaked OAuth2 bearer tokens when
following a redirect. This could result in tokens being sent to the wrong
host, contrary to expectations. This issue only affected Ubuntu 20.04 LTS.
(CVE-2026-3783)
Muhamad Arga Reksapati discovered that curl incorrectly reused existing
HTTP proxy connections even if the request used different credentials. This
could result in the use of incorrect credentials, contrary to expectations.
(CVE-2026-3784)
Update instructions
In general, a standard system update will make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 20.04 LTS focal | curl – 7.68.0-1ubuntu2.25+esm3 | ||
| libcurl3-gnutls – 7.68.0-1ubuntu2.25+esm3 | |||
| libcurl3-nss – 7.68.0-1ubuntu2.25+esm3 | |||
| libcurl4 – 7.68.0-1ubuntu2.25+esm3 | |||
| 18.04 LTS bionic | curl – 7.58.0-2ubuntu3.24+esm8 | ||
| libcurl3-gnutls – 7.58.0-2ubuntu3.24+esm8 | |||
| libcurl3-nss – 7.58.0-2ubuntu3.24+esm8 | |||
| libcurl4 – 7.58.0-2ubuntu3.24+esm8 | |||
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