CVE-2020-27171
Published: March 20, 2021Last modified: November 8, 2023
Description
An issue was discovered in the Linux kernel before 5.11.8. kernel/bpf/verifier.c has an off-by-one error (with a resultant integer underflow) affecting out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory, aka CID-10d2bb2e6b1d.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 6 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | HIGH |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Not affected (6.1.50-r0) |
| Stream | linux-lts | Not affected (6.1.50-r0) |
References
- http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html
- http://www.openwall.com/lists/oss-security/2021/03/24/5
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.8
- https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/patch/?id=10d2bb2e6b1d8c4576c56a748f697dbeb8388899
- https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FB6LUXPEIRLZH32YXWZVEZAD4ZL6SDK2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QRTPQE73ANG7D6M4L4PK5ZQDPO4Y2FVD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T2S3I4SLRNRUQDOFYUS6IUAZMQNMPNLG/
- https://www.openwall.com/lists/oss-security/2021/03/19/3