1. Ubuntu Security Notices
  2. USN-5079-1

USN-5079-1: curl vulnerabilities

Publication date

15 September 2021

Overview

Several security issues were fixed in curl.

Releases

Packages

  • curl - HTTP, HTTPS, and FTP client and client libraries

Details

It was discovered that curl incorrect handled memory when sending data to
an MQTT server. A remote attacker could use this issue to cause curl to
crash, resulting in a denial of service, or possibly execute arbitrary
code. (CVE-2021-22945)

Patrick Monnerat discovered that curl incorrectly handled upgrades to TLS.
When receiving certain responses from servers, curl would continue without
TLS even when the option to require a successful upgrade to TLS was
specified. (CVE-2021-22946)

Patrick Monnerat discovered that curl incorrectly handled responses
received before STARTTLS. A remote attacker could possibly use this issue
to inject responses and intercept communications. (CVE-2021-22947)

It was discovered that curl incorrect handled memory when sending data to
an MQTT server. A remote attacker could use this issue to cause curl to
crash, resulting in a denial of service, or possibly execute arbitrary
code. (CVE-2021-22945)

Patrick Monnerat discovered that curl incorrectly handled upgrades to TLS.
When receiving certain responses from servers, curl would continue without
TLS even when the option to require a successful upgrade to TLS was
specified. (CVE-2021-22946)

Patrick Monnerat discovered that curl incorrectly handled responses
received before STARTTLS. A remote attacker could possibly use this issue
to inject responses and intercept communications. (CVE-2021-22947)

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
21.04 hirsute libcurl3-gnutls –  7.74.0-1ubuntu2.3
libcurl3-nss –  7.74.0-1ubuntu2.3
libcurl4 –  7.74.0-1ubuntu2.3
curl –  7.74.0-1ubuntu2.3
20.04 focal libcurl3-gnutls –  7.68.0-1ubuntu2.7
libcurl3-nss –  7.68.0-1ubuntu2.7
libcurl4 –  7.68.0-1ubuntu2.7
curl –  7.68.0-1ubuntu2.7
18.04 bionic libcurl3-gnutls –  7.58.0-2ubuntu3.15
libcurl3-nss –  7.58.0-2ubuntu3.15
libcurl4 –  7.58.0-2ubuntu3.15
curl –  7.58.0-2ubuntu3.15

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References

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