In the Linux kernel 5.5.0 and newer, the bpf verifier (kernel/bpf/verifier.c) did not properly restrict the register bounds for 32-bit operations, leading to out-of-bounds reads and writes in kernel memory. The vulnerability also affects the Linux 5.4 stable series, starting with v5.4.7, as the introducing commit was backported to that branch. This vulnerability was fixed in 5.6.1, 5.5.14, and 5.4.29. (issue is aka ZDI-CAN-10780)
| Version | Base score | Base severity | Vector |
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| Hyperlink | Resource Type |
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In the Linux kernel 5.5.0 and newer, the bpf verifier (kernel/bpf/verifier.c) did not properly restrict the register bounds for 32-bit operations, leading to out-of-bounds reads and writes in kernel memory. The vulnerability also affects the Linux 5.4 stable series, starting with v5.4.7, as the introducing commit was backported to that branch. This vulnerability was fixed in 5.6.1, 5.5.14, and 5.4.29. (issue is aka ZDI-CAN-10780)
| Type | CWE ID | Description |
|---|---|---|
| text | N/A | n/a |
| Version | Base score | Base severity | Vector |
|---|---|---|---|
| 3.1 | 7.8 | HIGH | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H |
| CAPEC ID | Description |
|---|
Revert commit 581738a681b6 ("bpf: Provide better register bounds after jmp32 instructions").
Mitigation for this vulnerability is available by setting the kernel.unprivileged_bpf_disabled sysctl to 1: $ sudo sysctl kernel.unprivileged_bpf_disabled=1 $ echo kernel.unprivileged_bpf_disabled=1 | sudo tee /etc/sysctl.d/90-CVE-2020-8835.conf This issue is also mitigated on systems that use secure boot with the kernel lockdown feature which blocks BPF program loading.
| Event | Date |
|---|
| Version | Base score | Base severity | Vector |
|---|
| CAPEC ID | Description |
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| Event | Date |
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In the Linux kernel 5.5.0 and newer, the bpf verifier (kernel/bpf/verifier.c) did not properly restrict the register bounds for 32-bit operations, leading to out-of-bounds reads and writes in kernel memory. The vulnerability also affects the Linux 5.4 stable series, starting with v5.4.7, as the introducing commit was backported to that branch. This vulnerability was fixed in 5.6.1, 5.5.14, and 5.4.29. (issue is aka ZDI-CAN-10780)
| Date Added | Due Date | Vulnerability Name | Required Action |
|---|---|---|---|
| N/A |
| Type | Version | Base score | Base severity | Vector |
|---|---|---|---|---|
| Primary | 3.1 | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| Secondary | 3.1 | 7.8 | HIGH | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H |
| Primary | 2.0 | 7.2 | HIGH | AV:L/AC:L/Au:N/C:C/I:C/A:C |