CyberSecBulletin
CVE-2024-53142NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2024-53142 is a high-severity out-of-bounds write 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 bb7ac96670ab1d8d681015f9d66e45dad579af4d, c509b1acbd867d9e09580fe059a924cb5825afb1, d3df9f26cff97beaa5643e551031795d5d5cddbe 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 0.25% 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 bb7ac96670ab1d8d681015f9d66e45dad579af4d or c509b1acbd867d9e09580fe059a924cb5825afb1 or d3df9f26cff97beaa5643e551031795d5d5cddbe or 6983b8ac787b3add5571cda563574932a59a99bb, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 4.19.325 or 6.6.64 or 6.11.11 or 6.12.2, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, bb7ac96670ab1d8d681015f9d66e45dad579af4d; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, c509b1acbd867d9e09580fe059a924cb5825afb1; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, d3df9f26cff97beaa5643e551031795d5d5cddbe; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 6983b8ac787b3add5571cda563574932a59a99bb; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, f892ddcf9f645380c358e73653cb0900f6bc9eb8; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 1a423bbbeaf9e3e20c4686501efd9b661fe834db; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 49d01e736c3045319e030d1e75fb983011abaca7; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, fb83b093f75806333b6f4ae29b158d2e0e3ec971; and 2 more rangesbb7ac96670ab1d8d681015f9d66e45dad579af4d, c509b1acbd867d9e09580fe059a924cb5825afb1, d3df9f26cff97beaa5643e551031795d5d5cddbe, 6983b8ac787b3add5571cda563574932a59a99bb, f892ddcf9f645380c358e73653cb0900f6bc9eb8, 1a423bbbeaf9e3e20c4686501efd9b661fe834db
LinuxLinux Kernel2.6.12 up to, but not including, 4.19.325; 4.20 up to, but not including, 6.6.64; 6.7 up to, but not including, 6.11.11; 6.12 up to, but not including, 6.12.24.19.325, 6.6.64, 6.11.11, 6.12.2

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: initramfs: avoid filename buffer overrun The initramfs filename field is defined in Documentation/driver-api/early-userspace/buffer-format.rst as: 37 cpio_file := ALGN(4) + cpio_header + filename + "\0" + ALGN(4) + data ... 55 ============= ================== ========================= 56 Field name Field size Meaning 57 ============= ================== ========================= ... 70 c_namesize 8 bytes Length of filename, including final \0 When extracting an initramfs cpio archive, the kernel's do_name() path handler assumes a zero-terminated path at @collected, passing it directly to filp_open() / init_mkdir() / init_mknod(). If a specially crafted cpio entry carries a non-zero-terminated filename and is followed by uninitialized memory, then a file may be created with trailing characters that represent the uninitialized memory. The ability to create an initramfs entry would imply already having full control of the system, so the buffer overrun shouldn't be considered a security vulnerability. Append the output of the following bash script to an existing initramfs and observe any created /initramfs_test_fname_overrunAA* path. E.g. ./reproducer.sh | gzip >> /myinitramfs It's easiest to observe non-zero uninitialized memory when the output is gzipped, as it'll overflow the heap allocated @out_buf in __gunzip(), rather than the initrd_start+initrd_size block. ---- reproducer.sh ---- nilchar="A" # change to "\0" to properly zero terminate / pad magic="070701" ino=1 mode=$(( 0100777 )) uid=0 gid=0 nlink=1 mtime=1 filesize=0 devmajor=0 devminor=1 rdevmajor=0 rdevminor=0 csum=0 fname="initramfs_test_fname_overrun" namelen=$(( ${#fname} + 1 )) # plus one to account for terminator printf "%s%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%s" \ $magic $ino $mode $uid $gid $nlink $mtime $filesize \ $devmajor $devminor $rdevmajor $rdevminor $namelen $csum $fname termpadlen=$(( 1 + ((4 - ((110 + $namelen) & 3)) % 4) )) printf "%.s${nilchar}" $(seq 1 $termpadlen) ---- reproducer.sh ---- Symlink filename fields handled in do_symlink() won't overrun past the data segment, due to the explicit zero-termination of the symlink target. Fix filename buffer overrun by aborting the initramfs FSM if any cpio entry doesn't carry a zero-terminator at the expected (name_len - 1) offset.

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

The underlying weakness: Out-of-bounds Write

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

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

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

References

Recent Out-of-bounds Write vulnerabilities

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