Vulnerability Description
An issue was discovered in the Linux kernel through 5.11.x. kernel/bpf/verifier.c performs undesirable out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory. Specifically, for sequences of pointer arithmetic operations, the pointer modification performed by the first operation is not correctly accounted for when restricting subsequent operations.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | < 5.11.16 |
| Fedoraproject | Fedora | 32 |
| Debian | Debian Linux | 9.0 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=07381
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=24c10
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6f55b
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7fedb
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=96011
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=a6aae
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b658b
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f5288
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.htmlMailing ListThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://www.kernel.orgVendor Advisory
- https://www.openwall.com/lists/oss-security/2021/04/18/4Mailing ListPatchThird Party Advisory
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=07381
FAQ
What is CVE-2021-29155?
CVE-2021-29155 is a vulnerability with a CVSS score of 5.5 (MEDIUM). An issue was discovered in the Linux kernel through 5.11.x. kernel/bpf/verifier.c performs undesirable out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spec...
How severe is CVE-2021-29155?
CVE-2021-29155 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-29155?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel, Fedoraproject Fedora, Debian Debian Linux.