9.8

CVE-2021-27431: arm cmsis rtos2 Integer Overflow or Wraparound

CVSS: 9.8v3.1CriticalModified
Published 03-05-2022Last modified 16-04-2025

Vulnerability summary

CVE-2021-27431 is a critical (CVSS 9.8) Integer Overflow or Wraparound vulnerability in arm cmsis rtos2. EPSS estimates a 1.15% chance of exploitation in the next 30 days, higher than 66.3% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (NVD)
EPSS score
1.15%
0%100%
Low · +0.04 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 03-05-2022
    PublishedVulnerability first disclosed.
  2. 16-04-2025
    Last modifiedVulnerability information updated.

Description

ARM CMSIS RTOS2 versions prior to 2.1.3 are vulnerable to integer wrap-around inosRtxMemoryAlloc (local malloc equivalent) function, which can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash or injected code execution.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

1.15%

Chance of exploitation in the next 30 days

Percentile

66%

Versus all other CVEs

30-day change

+0.04 pp

From 1.10% on 20-09-2026

20-09-202620-10-2026
EPSS score
1.15%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Arm2 products

1 vendor · 2 products

References

1 links