CVE-2023-0266
Description
A use-after-free flaw was found in snd_ctl_elem_read in sound/core/control.c in Advanced Linux Sound Architecture (ALSA) subsystem in the Linux kernel. In this flaw a normal privileged, local attacker may impact the system due to a locking issue in the compat path, leading to a kernel information leak problem.
Mitigation
To mitigate this issue, skip loading (blacklist) the affected soundcard using modules like:
blacklist soundcore
blacklist snd
blacklist snd_pcm
blacklist snd_hda_codec_hdmi
blacklist snd_hda_codec_realtek
blacklist snd_hda_codec_generic
blacklist snd_hda_intel
blacklist snd_hda_codec
blacklist snd_hda_core
blacklist snd_hwdep
blacklist snd_timer
onto the system till we have a fix available.
This can be done by a blacklist mechanism, this will ensure the driver is not loaded at the boot time.
How do I blacklist a kernel module to prevent it from loading automatically?
https://access.redhat.com/solutions/41278
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 | 7.8 | 7 | 7.9 |
| Attack Vector | Local | Local | Adjacent Network |
| Attack Complexity | Low | High | High |
| Privileges Required | Low | Low | Low |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Changed |
| Confidentiality | High | High | Low |
| Integrity Impact | High | High | High |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:C/C:L/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory
The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.
Confidentiality
Technical Impact: Read Memory
Read operations on freed memory can sometimes leak sensitive information instead of causing a crash
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
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