CVE-2021-3600

Published: 22 June 2021

It was discovered that the eBPF implementation in the Linux kernel did not properly track bounds information for 32 bit registers when performing div and mod operations. A local attacker could use this to possibly execute arbitrary code.

From the Ubuntu security team

It was discovered that the eBPF implementation in the Linux kernel did not properly track bounds information for 32 bit registers when performing div and mod operations. A local attacker could use this to possibly execute arbitrary code.

Status

Notes

4.15 kernels the only ubuntu kernels that have not yet had
the fix applied
for 4.15 kernels, f6b1b3bf0d5f ("bpf: fix subprog verifier
bypass by div/mod by 0 exception") is needed as a prerequisite but
introduces CVE-2021-3444

Commit f1174f77b50c is also necessary to exploit, and is
not present on 4.4 kernels.

References

• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3600
• https://git.kernel.org/linus/e88b2c6e5a4d9ce30d75391e4d950da74bb2bd90
• https://ubuntu.com/security/notices/USN-5003-1
• NVD
• Launchpad
• Debian

Bugs