CVE-2021-31440

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.

Weakness

The product performs a calculation that generates incorrect or unintended results that are later used in security-critical decisions or resource management.

Affected Software

Potential Mitigations

• Use languages, libraries, or frameworks that make it easier to handle numbers without unexpected consequences.
• Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++).
• Use languages, libraries, or frameworks that make it easier to handle numbers without unexpected consequences.
• Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++).

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/128.html
• https://cwe.mitre.org/data/definitions/129.html

References

• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=10bf4e83167cc68595b85fd73bb91e8f2c086e36
• https://security.netapp.com/advisory/ntap-20210706-0003/
• https://www.zerodayinitiative.com/advisories/ZDI-21-503/
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=10bf4e83167cc68595b85fd73bb91e8f2c086e36
• https://security.netapp.com/advisory/ntap-20210706-0003/
• https://www.zerodayinitiative.com/advisories/ZDI-21-503/