Vulnerability · Published May 21, 2021 · Assigned by zdi
CVE-2021-31440
High 8.8
In plain English
A high-severity security flaw in Kernel from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.8% (higher than 78% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel 5.11.15. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handling of eBPF programs. The issue results from the lack of proper validation of user-supplied eBPF programs prior to executing them. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the kernel. Was ZDI-CAN-13661.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | kernel-tools-libs-devel | 4.18.0-348.el8 | ALSA-2021:4356 |
| Debian:12 | linux | 5.10.38-1 | DEBIAN-CVE-2021-31440 |
| Debian:13 | linux | 5.10.38-1 | DEBIAN-CVE-2021-31440 |
| Debian:14 | linux | 5.10.38-1 | DEBIAN-CVE-2021-31440 |
Affected products (as reported)
Weakness: CWE-682 · Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H