CVE-2010-2524: Canonical Ubuntu Linux

High severity, CVSS 7.8. EPSS: 0.4% chance of exploitation in the next 30 days.

The DNS resolution functionality in the CIFS implementation in the Linux kernel before 2.6.35, when CONFIG_CIFS_DFS_UPCALL is enabled, relies on a user's keyring for the dns_resolver upcall in the cifs.upcall userspace helper, which allows local users to spoof the results of DNS queries and perform arbitrary CIFS mounts via vectors involving an add_key call, related to a "cache stuffing" issue and MS-DFS referrals.

Affected products

• Canonical Ubuntu Linux: version 6.06 only; version 8.04 only; version 9.04 only; version 9.10 only; version 10.04 only; version 10.10 only
• Linux Linux Kernel: before 2.6.35 (fixed in 2.6.35)
• Suse Suse Linux Enterprise Desktop: version 11 only
• Suse Suse Linux Enterprise Server: version 11 only
• VMware Esx: version 4.0 only; version 4.1 only

Published 2010-09-08. Last modified 2026-06-16.