CVE-2015-2666: Buffer Overflow
It was found that the Linux kernel's Intel early microcode loader was vulnerable to a stack overflow.
On a UEFI Secure Boot enabled system, a local root user could use this flaw to increase their privileges to the kernel (ring0) level despite the additional restrictions in place.
Upstream fix:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit?id=f84598bd7c851f8b0bf8cd0d7c3be0d73c432ff4
Other sources
Stack-based buffer overflow in the getmatchingmodelmicrocode function in arch/x86/kernel/cpu/microcode/intelearly.c in the Linux kernel before 4.0 allows context-dependent attackers to gain privileges by constructing a crafted microcode header and leveraging root privileges for write access to the initrd.
— Launchpad
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2015-2666?
CVE-2015-2666 is classified as a high-severity vulnerability due to its potential for local privilege escalation.
How do I fix CVE-2015-2666?
To fix CVE-2015-2666, update the Linux kernel to a version that is not affected, such as 5.10.223-1 or later.
Which versions of the Linux kernel are affected by CVE-2015-2666?
CVE-2015-2666 affects Linux kernel versions between 3.9 to 3.19.8, including several specific versions in that range.
Can CVE-2015-2666 be exploited on systems with UEFI Secure Boot enabled?
Yes, CVE-2015-2666 can be exploited by a local root user on systems with UEFI Secure Boot enabled to escalate privileges.
What is the impact of CVE-2015-2666?
The impact of CVE-2015-2666 is that it allows a local attacker to gain kernel-level privileges, potentially leading to a full system compromise.