CyberSecBulletin
CVE-2022-49515NVD status: Analyzed

Linux: Out-of-bounds Read

CVE-2022-49515 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions dbc35268e14d5d89c7a9db72009ad4dcd9ede646, a59b9958416096dd21dc4f62b0c5be525d459ca8, 9f342904216f378e88008bb0ce1ae200a4b99fe8 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.27% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to dbc35268e14d5d89c7a9db72009ad4dcd9ede646 or a59b9958416096dd21dc4f62b0c5be525d459ca8 or 9f342904216f378e88008bb0ce1ae200a4b99fe8, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.17.14 or 5.18.3, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux6450ef55905688602175fae4ed1bfbfef6a14dde up to, but not including, dbc35268e14d5d89c7a9db72009ad4dcd9ede646; 6450ef55905688602175fae4ed1bfbfef6a14dde up to, but not including, a59b9958416096dd21dc4f62b0c5be525d459ca8; 6450ef55905688602175fae4ed1bfbfef6a14dde up to, but not including, 9f342904216f378e88008bb0ce1ae200a4b99fe8; 5.16dbc35268e14d5d89c7a9db72009ad4dcd9ede646, a59b9958416096dd21dc4f62b0c5be525d459ca8, 9f342904216f378e88008bb0ce1ae200a4b99fe8
LinuxLinux Kernel5.16 up to, but not including, 5.17.14; 5.18 up to, but not including, 5.18.35.17.14, 5.18.3

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.

Official description

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 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

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Read vulnerabilities

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