CVE-2023-52476
Description
From CVE.org
In the Linux kernel, the following vulnerability has been resolved: perf/x86/lbr: Filter vsyscall addresses We found that a panic can occur when a vsyscall is made while LBR sampling is active. If the vsyscall is interrupted (NMI) for perf sampling, this call sequence can occur (most recent at top): __insn_get_emulate_prefix() insn_get_emulate_prefix() insn_get_prefixes() insn_get_opcode() decode_branch_type() get_branch_type() intel_pmu_lbr_filter() intel_pmu_handle_irq() perf_event_nmi_handler() Within __insn_get_emulate_prefix() at frame 0, a macro is called: peek_nbyte_next(insn_byte_t, insn, i) Within this macro, this dereference occurs: (insn)->next_byte Inspecting registers at this point, the value of the next_byte field is the address of the vsyscall made, for example the location of the vsyscall version of gettimeofday() at 0xffffffffff600000. The access to an address in the vsyscall region will trigger an oops due to an unhandled page fault. To fix the bug, filtering for vsyscalls can be done when determining the branch type. This patch will return a "none" branch if a kernel address if found to lie in the vsyscall region.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability,Other
Technical Impact: DoS: Resource Consumption (Other); Varies by Context
Most unreleased resource issues result in general software reliability problems, but if an attacker can intentionally trigger a resource leak, the attacker might be able to launch a denial of service attack by depleting the resource pool.
Confidentiality
Technical Impact: Read Application Data
When a resource containing sensitive information is not correctly shutdown, it may expose the sensitive data in a subsequent allocation.
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