CVE-2022-49515
Published: 26 February 2025
Summary
CVE-2022-49515 is a high-severity Out-of-bounds Read (CWE-125) vulnerability in Linux Linux Kernel. Its CVSS base score is 7.1 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 33.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and CM-7 (Least Functionality).
Deeper analysis
CVE-2022-49515 is an out-of-bounds access vulnerability in the Linux kernel's ASoC (ALSA System on Chip) subsystem, specifically affecting the CS35L41 audio codec driver. The issue arises because the constant CS35L41_NUM_OTP_ELEM is defined as 100, but the arrays otp_map_1 and otp_map_2 only contain 99 entries. This mismatch triggers a shift-out-of-bounds condition in the cs35l41_otp_unpack() function, as reported by UBSAN, when processing the last entry via GENMASK(-1, 0). The vulnerability was observed in kernel version 5.15.0-23-generic during probing of the snd_hda_scodec_cs35l41 module.
A local attacker with low privileges (PR:L) can exploit this vulnerability with low attack complexity (AC:L) and no user interaction (UI:N), requiring local access (AV:L) to the system. Successful exploitation leads to high confidentiality impact (C:H) through potential out-of-bounds reads (CWE-125) and high availability impact (A:H), likely causing denial of service via crashes or memory corruption, with no integrity impact (I:N) and no scope change (S:U). The CVSS v3.1 base score is 7.1.
Mitigation involves applying patches from the Linux kernel stable trees, as detailed in the referenced commits: 9f342904216f378e88008bb0ce1ae200a4b99fe8, a59b9958416096dd21dc4f62b0c5be525d459ca8, and dbc35268e14d5d89c7a9db72009ad4dcd9ede646. These fixes address the array size discrepancy in the CS35L41 driver to prevent the UBSAN-reported shift-out-of-bounds error.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2022-54714
Vulnerability details
In the Linux kernel, the following vulnerability has been resolved: ASoC: cs35l41: Fix an out-of-bounds access in otp_packed_element_t The CS35L41_NUM_OTP_ELEM is 100, but only 99 entries are defined in the array otp_map_1/2[CS35L41_NUM_OTP_ELEM], this will trigger UBSAN to report a shift-out-of-bounds…
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warning in the cs35l41_otp_unpack() since the last entry in the array will result in GENMASK(-1, 0). UBSAN reports this problem: UBSAN: shift-out-of-bounds in /home/hwang4/build/jammy/jammy/sound/soc/codecs/cs35l41-lib.c:836:8 shift exponent 64 is too large for 64-bit type 'long unsigned int' CPU: 10 PID: 595 Comm: systemd-udevd Not tainted 5.15.0-23-generic #23 Hardware name: LENOVO \x02MFG_IN_GO/\x02MFG_IN_GO, BIOS N3GET19W (1.00 ) 03/11/2022 Call Trace: <TASK> show_stack+0x52/0x58 dump_stack_lvl+0x4a/0x5f dump_stack+0x10/0x12 ubsan_epilogue+0x9/0x45 __ubsan_handle_shift_out_of_bounds.cold+0x61/0xef ? regmap_unlock_mutex+0xe/0x10 cs35l41_otp_unpack.cold+0x1c6/0x2b2 [snd_soc_cs35l41_lib] cs35l41_hda_probe+0x24f/0x33a [snd_hda_scodec_cs35l41] cs35l41_hda_i2c_probe+0x65/0x90 [snd_hda_scodec_cs35l41_i2c] ? cs35l41_hda_i2c_remove+0x20/0x20 [snd_hda_scodec_cs35l41_i2c] i2c_device_probe+0x252/0x2b0
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Local kernel OOB read in audio driver enables privilege escalation (T1068), credential/info disclosure via memory leak (T1212), and system crash/DoS via exploitation (T1499.004).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly remediates the array bounds mismatch in the CS35L41 driver by applying specific kernel patches, preventing the out-of-bounds shift condition.
Restricts loading of unnecessary kernel modules like snd_soc_cs35l41_lib, avoiding exposure to the vulnerable driver during device probing.
Implements kernel memory protections such as ASLR or SMEP to mitigate potential exploitation of the out-of-bounds access for DoS or information disclosure.