USN-4017-1: Linux kernel vulnerabilities
Severity
High
Vendor
Canonical Ubuntu
Versions Affected
- Canonical Ubuntu 16.04
Description
Jonathan Looney discovered that the TCP retransmission queue implementation in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. (CVE-2019-11478)
Jonathan Looney discovered that an integer overflow existed in the Linux kernel when handling TCP Selective Acknowledgments (SACKs). A remote attacker could use this to cause a denial of service (system crash). (CVE-2019-11477)
CVEs contained in this USN include: CVE-2019-11477, CVE-2019-11478
Affected Cloud Foundry Products and Versions
Severity is high unless otherwise noted.
- Cloud Foundry BOSH xenial-stemcells are vulnerable, including:
- 315.x versions prior to 315.41
- 250.x versions prior to 250.63
- 170.x versions prior to 170.93
- 97.x versions prior to 97.113
- All other stemcells not listed.
Mitigation
Users of affected products are strongly encouraged to follow one of the mitigations below:
- The Cloud Foundry project recommends upgrading the following BOSH xenial-stemcells:
- Upgrade 315.x versions to 315.41
- Upgrade 250.x versions to 250.63
- Upgrade 170.x versions to 170.93
- Upgrade 97.x versions to 97.113
- All other stemcells should be upgraded to the latest version available on bosh.io.
References