7.1

CVE-2024-50279: dm cache: fix out-of-bounds access to the dirty bitset when resizing

Modified
AliasesUBUNTU-CVE-2024-50279DEBIAN-CVE-2024-50279
Published 19-11-2024Last modified 11-05-2026

Vulnerability summary

CVE-2024-50279 is a high (CVSS 7.1) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 18% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.1, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.26%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 100 · Related 99
DLA-4008-1DLA-4075-1DSA-5818-1SUSE-SU-2024:4313-1SUSE-SU-2024:4314-1SUSE-SU-2024:4315-1

Showing 100 of 102.

Timeline

  1. 19-11-2024
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: dm cache: fix out-of-bounds access to the dirty bitset when resizing dm-cache checks the dirty bits of the cache blocks to be dropped when shrinking the fast device, but an index bug in bitset iteration causes out-of-bounds access. Reproduce steps: 1. create a cache device of 1024 cache blocks (128 bytes dirty bitset) dmsetup create cmeta --table "0 8192 linear /dev/sdc 0" dmsetup create cdata --table "0 131072 linear /dev/sdc 8192" dmsetup create corig --table "0 524288 linear /dev/sdc 262144" dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0" 2. shrink the fast device to 512 cache blocks, triggering out-of-bounds access to the dirty bitset (offset 0x80) dmsetup suspend cache dmsetup reload cdata --table "0 65536 linear /dev/sdc 8192" dmsetup resume cdata dmsetup resume cache KASAN reports: BUG: KASAN: vmalloc-out-of-bounds in cache_preresume+0x269/0x7b0 Read of size 8 at addr ffffc900000f3080 by task dmsetup/131 (...snip...) The buggy address belongs to the virtual mapping at [ffffc900000f3000, ffffc900000f5000) created by: cache_ctr+0x176a/0x35f0 (...snip...) Memory state around the buggy address: ffffc900000f2f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc900000f3000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc900000f3080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffffc900000f3100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc900000f3180: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 Fix by making the index post-incremented.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

18%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.26% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu134 products
  • linuxAll versions (No fix recorded) | < 5.4.0-208.228 | < 5.15.0-133.144 | < 6.8.0-58.60
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.4.0-1140.150 | < 5.15.0-1078.85 | < 6.8.0-1027.29
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 4fa4feb873cea0e9d6ff883b37cca6f33169d8b4 | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 8501e38dc9e0060814c4085815fc83da3e6d43bf | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < ee1f74925717ab36f6a091104c170639501ce818 | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < ff1dd8a04c30e8d4e2fd5c83198ca672eb6a9e7f | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 56507203e1b6127967ec2b51fb0b23a0d4af1334 | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < e57648ce325fa405fe6bbd0e6a618ced7c301a2d | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 3b02c40ff10fdf83cc545850db208de855ebe22c | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 792227719725497ce10a8039803bec13f89f8910 | 3.13
  • linux_kernel≥ 3.13, < 4.19.324 | ≥ 4.20, < 5.4.286 | ≥ 5.5, < 5.10.230 | ≥ 5.11, < 5.15.172 | ≥ 5.16, < 6.1.117 | ≥ 6.2, < 6.6.61 | ≥ 6.7, < 6.11.8 | 6.12:rc1 | 6.12:rc2 | 6.12:rc3 | 6.12:rc4 | 6.12:rc5 | 6.12:rc6
Debian1 product
  • linux< 6.1.119-1 | < 6.11.9-1

3 vendors · 137 products

References

52 links
Show all 52 references