CVE-2023-52733

2024-05-2116:15:13

416baaa9-dc9f-4396-8d5f-8c081fb06d67

web.nvd.nist.gov

linux kernel

s390 decompressor

vulnerability

resolved

uncompressed kernel

image

specify

out_len parameter

corruption

nvd

7 High

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.6%

JSON

In the Linux kernel, the following vulnerability has been resolved:

s390/decompressor: specify __decompress() buf len to avoid overflow

Historically calls to __decompress() didn’t specify “out_len” parameter
on many architectures including s390, expecting that no writes beyond
uncompressed kernel image are performed. This has changed since commit
2aa14b1ab2c4 (“zstd: import usptream v1.5.2”) which includes zstd library
commit 6a7ede3dfccb (“Reduce size of dctx by reutilizing dst buffer
(#2751)”). Now zstd decompression code might store literal buffer in
the unwritten portion of the destination buffer. Since “out_len” is
not set, it is considered to be unlimited and hence free to use for
optimization needs. On s390 this might corrupt initrd or ipl report
which are often placed right after the decompressor buffer. Luckily the
size of uncompressed kernel image is already known to the decompressor,
so to avoid the problem simply specify it in the “out_len” parameter.

Affected configurations

Vulners

Node

linuxlinux_kernelRange5.4.0–5.4.232

linuxlinux_kernelRange5.5.0–5.10.169

linuxlinux_kernelRange5.11.0–5.15.95

linuxlinux_kernelRange5.16.0–6.1.13

linuxlinux_kernelRange6.2.0≥

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "arch/s390/boot/decompressor.c"
    ],
    "versions": [
      {
        "version": "1da177e4c3f4",
        "lessThan": "16409f7d9ca5",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "55dbd6f4ea95",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "9ed522143f95",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "f1eb22d0ff06",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "7ab41c2c08a3",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "arch/s390/boot/decompressor.c"
    ],
    "versions": [
      {
        "version": "5.4.232",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.169",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.95",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.13",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.2",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]