CVE-2021-33033
High
CVE-2021-33033
The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads to writing an arbitrary value.
Exploit probability
0.6%
Published
May 14, 2021
Required by
Not available
Last source change
March 14, 2026
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
Open Source Vulnerabilities
CVE-2021-33033
View original source
The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads to writing an arbitrary value.
05 / REFERENCES
Further evidence
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.14
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.7
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1165affd484889d4986cf3b724318935a0b120d8
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ad5d07f4a9cd671233ae20983848874731102c08
- https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-cipso_v4_genopt
- https://syzkaller.appspot.com/bug?id=96e7d345748d8814901c91cd92084ed04b46701e