CVE-2021-27433

ARM mbed-ualloc memory library Integer Overflow or Wraparound

Description

ARM mbed-ualloc memory library version 1.3.0 is vulnerable to integer wrap-around in function mbed_krbs, which can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash or a remote code injection/execution.

Remediation

Solution:

  • ARM Mbed OS update available.

Category

7.3
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 3.78% Top 15%
Third-Party Advisory github.com Third-Party Advisory cisa.gov
Affected: ARM mbed-ualloc memory library
Published at:
Updated at:

References

Link Tags
https://www.cisa.gov/uscert/ics/advisories/icsa-21-119-04 third party advisory us government resource
https://github.com/ARMmbed/mbed-os/pull/14408 issue tracking third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-27433?
CVE-2021-27433 has been scored as a high severity vulnerability.
How to fix CVE-2021-27433?
To fix CVE-2021-27433: ARM Mbed OS update available.
Is CVE-2021-27433 being actively exploited in the wild?
It is possible that CVE-2021-27433 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~4% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-27433?
CVE-2021-27433 affects ARM mbed-ualloc memory library.
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