5.5

CVE-2021-47231: can: mcba_usb: fix memory leak in mcba_usb

Analyzed
AliasesUBUNTU-CVE-2021-47231DEBIAN-CVE-2021-47231
Published 21-05-2024Last modified 11-05-2026

Vulnerability summary

CVE-2021-47231 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.3% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.23%
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 7 · Related 7
SUSE-SU-2024:1979-1SUSE-SU-2024:1983-1SUSE-SU-2024:2010-1SUSE-SU-2024:2183-1SUSE-SU-2024:2184-1SUSE-SU-2024:2185-1

Timeline

  1. 21-05-2024
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: can: mcba_usb: fix memory leak in mcba_usb Syzbot reported memory leak in SocketCAN driver for Microchip CAN BUS Analyzer Tool. The problem was in unfreed usb_coherent. In mcba_usb_start() 20 coherent buffers are allocated and there is nothing, that frees them: 1) In callback function the urb is resubmitted and that's all 2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER is not set (see mcba_usb_start) and this flag cannot be used with coherent buffers. Fail log: | [ 1354.053291][ T8413] mcba_usb 1-1:0.0 can0: device disconnected | [ 1367.059384][ T8420] kmemleak: 20 new suspected memory leaks (see /sys/kernel/debug/kmem) So, all allocated buffers should be freed with usb_free_coherent() explicitly NOTE: The same pattern for allocating and freeing coherent buffers is used in drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

13%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.23% 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.

Ubuntu85 products
  • linux< 4.15.0-156.163 | < 5.4.0-81.91
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.15.0-1111.118 | < 5.4.0-1055.58
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 51f3baad7de943780ce0c17bd7975df567dd6e14, < 89df95ce32be204eef2e7d4b2f6fb552fb191a68 | ≥ 51f3baad7de943780ce0c17bd7975df567dd6e14, < a115198caaab6d663bef75823a3c5f0802306d60 | ≥ 51f3baad7de943780ce0c17bd7975df567dd6e14, < 6f87c0e21ad20dd3d22108e33db1c552dfa352a0 | ≥ 51f3baad7de943780ce0c17bd7975df567dd6e14, < 6bd3d80d1f019cefa7011056c54b323f1d8b8e83 | ≥ 51f3baad7de943780ce0c17bd7975df567dd6e14, < d0760a4ef85697bc756d06eae17ae27f3f055401 | ≥ 51f3baad7de943780ce0c17bd7975df567dd6e14, < 91c02557174be7f72e46ed7311e3bea1939840b0 | 4.12
  • linux_kernel≥ 4.12, < 4.14.238 | ≥ 4.15, < 4.19.196 | ≥ 4.20, < 5.4.128 | ≥ 5.5, < 5.10.46 | ≥ 5.11, < 5.12.13 | 5.13:rc1 | 5.13:rc2 | 5.13:rc3 | 5.13:rc4 | 5.13:rc5 | 5.13:rc6
Debian1 product
  • linux< 5.10.46-1

3 vendors · 88 products

References

10 links