#VU52035 Use-after-free in Linux kernel - CVE-2021-3347
Vulnerability identifier: #VU52035
Vulnerability risk: Low
CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]
CVE-ID: CVE-2021-3347
CWE-ID:
CWE-416
Exploitation vector: Local
Exploit availability: No
Vulnerable software:
Linux kernel
Operating systems & Components /
Operating system
Vendor: Linux Foundation
Description
The vulnerability allows a local user to elevate privileges on the system.
The vulnerability exists due to a use-after-free error when handling PI futexes. A local user can run a specially crafted program to trigger a use-after-free error and execute arbitrary code with elevated privileges.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
Linux kernel: before 5.10.11, 5.10.11
External links
https://www.openwall.com/lists/oss-security/2021/01/29/4
https://www.openwall.com/lists/oss-security/2021/01/29/5
https://www.openwall.com/lists/oss-security/2021/02/01/4
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=04b79c55201f02ffd675e1231d731365e335c307
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=12bb3f7f1b03d5913b3f9d4236a488aa7774dfe9
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2156ac1934166d6deb6cd0f6ffc4c1076ec63697
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=34b1a1ce1458f50ef27c54e28eb9b1947012907a
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6ccc84f917d33312eb2846bd7b567639f585ad6d
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c5cade200ab9a2a3be9e7f32a752c8d86b502ec7
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c64396cc36c6e60704ab06c1fb1c4a46179c9120
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f2dac39d93987f7de1e20b3988c8685523247ae2
https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CXAVDAK4RLAHBHHGEPL73UFXSI6BXQ7Q/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QOBMXDJABYE76RKNBAWA2E4TSSBX7CSJ/
https://security.netapp.com/advisory/ntap-20210304-0005/
https://www.debian.org/security/2021/dsa-4843
https://www.openwall.com/lists/oss-security/2021/01/29/1
https://www.openwall.com/lists/oss-security/2021/01/29/3
Q & A
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
