CyberSecBulletin
CVE-2024-42136NVD status: Analyzed

Linux: Integer Overflow or Wraparound

Published Updated By the CyberSecBulletin desk

CVE-2024-42136 is a high-severity integer overflow or wraparound vulnerability in Linux, with a CVSS 3.1 base score of 7.8 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 0c97527e916054acc4a46ffb02842988acb2e92b, 3ee21e14c8c329168a0b66bab00ecd18f5d0dee3, e809bc112712da8f7e15822674c6562da6cdf24c 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 0.23% 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 0c97527e916054acc4a46ffb02842988acb2e92b or 3ee21e14c8c329168a0b66bab00ecd18f5d0dee3 or e809bc112712da8f7e15822674c6562da6cdf24c or efb905aeb44b0e99c0e6b07865b1885ae0471ebf, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.1.98 or 6.6.39 or 6.9.9, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux67f1e027c27054e641584655020a417eaac9cb3a up to, but not including, 0c97527e916054acc4a46ffb02842988acb2e92b; 67f1e027c27054e641584655020a417eaac9cb3a up to, but not including, 3ee21e14c8c329168a0b66bab00ecd18f5d0dee3; 67f1e027c27054e641584655020a417eaac9cb3a up to, but not including, e809bc112712da8f7e15822674c6562da6cdf24c; 67f1e027c27054e641584655020a417eaac9cb3a up to, but not including, efb905aeb44b0e99c0e6b07865b1885ae0471ebf; 5.160c97527e916054acc4a46ffb02842988acb2e92b, 3ee21e14c8c329168a0b66bab00ecd18f5d0dee3, e809bc112712da8f7e15822674c6562da6cdf24c, efb905aeb44b0e99c0e6b07865b1885ae0471ebf
DebianDebian Linux11.0Not stated
LinuxLinux Kernel5.16 up to, but not including, 6.1.98; 6.2 up to, but not including, 6.6.39; 6.7 up to, but not including, 6.9.96.1.98, 6.6.39, 6.9.9

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
HighData or code can be modified at will.
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:H/A:H. Scored by NVD.

Official description

In the Linux kernel, the following vulnerability has been resolved: cdrom: rearrange last_media_change check to avoid unintentional overflow When running syzkaller with the newly reintroduced signed integer wrap sanitizer we encounter this splat: [ 366.015950] UBSAN: signed-integer-overflow in ../drivers/cdrom/cdrom.c:2361:33 [ 366.021089] -9223372036854775808 - 346321 cannot be represented in type '__s64' (aka 'long long') [ 366.025894] program syz-executor.4 is using a deprecated SCSI ioctl, please convert it to SG_IO [ 366.027502] CPU: 5 PID: 28472 Comm: syz-executor.7 Not tainted 6.8.0-rc2-00035-gb3ef86b5a957 #1 [ 366.027512] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 366.027518] Call Trace: [ 366.027523] <TASK> [ 366.027533] dump_stack_lvl+0x93/0xd0 [ 366.027899] handle_overflow+0x171/0x1b0 [ 366.038787] ata1.00: invalid multi_count 32 ignored [ 366.043924] cdrom_ioctl+0x2c3f/0x2d10 [ 366.063932] ? __pm_runtime_resume+0xe6/0x130 [ 366.071923] sr_block_ioctl+0x15d/0x1d0 [ 366.074624] ? __pfx_sr_block_ioctl+0x10/0x10 [ 366.077642] blkdev_ioctl+0x419/0x500 [ 366.080231] ? __pfx_blkdev_ioctl+0x10/0x10 ... Historically, the signed integer overflow sanitizer did not work in the kernel due to its interaction with `-fwrapv` but this has since been changed [1] in the newest version of Clang. It was re-enabled in the kernel with Commit 557f8c582a9ba8ab ("ubsan: Reintroduce signed overflow sanitizer"). Let's rearrange the check to not perform any arithmetic, thus not tripping the sanitizer.

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

The underlying weakness: Integer Overflow or Wraparound

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

How developers prevent this class of flaw

  • Ensure that all protocols are strictly defined, such that all out-of-bounds behavior can be identified simply, and require strict conformance to the protocol.
  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. If possible, choose a language or compiler that performs automatic bounds checking.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Use libraries or frameworks that make it easier to handle numbers without unexpected consequences. Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++).

More Integer Overflow or Wraparound vulnerabilities (CWE-190)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Recent Integer Overflow or Wraparound vulnerabilities

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