PatchTheCVECVE-2021-26461: Apache Nuttx Versions prior to 10.1.0 are vulnerable to integer wrap-around in functions malloc, realloc and m
CVE-2021-26461 is a critical-severity flaw (CVSS 9.8) affecting nuttx. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Apache Nuttx Versions prior to 10.1.0 are vulnerable to integer wrap-around in functions malloc, realloc and memalign. This improper memory assignment can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash or a remote code injection/execution.
Why this priority
- Critical severity
- EPSS top 8%: very likely to be exploited
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 5.0% (top 8%) |
| CISA exploited list | No |
| Weakness | CWE-190 |
| Published | 2021-06-21 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2021-26461?
nuttx: upgrade to 10.1.0. Exact commands for each OS are on this page.
Is CVE-2021-26461 being exploited?
CVE-2021-26461 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2021-26461 affect?
CVE-2021-26461 affects nuttx. Severity is critical (CVSS 9.8). Apache Nuttx Versions prior to 10.1.0 are vulnerable to integer wrap-around in functions malloc, realloc and memalign. This improper memory assignment can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash
How urgent is CVE-2021-26461?
Priority 67/100. Critical severity; EPSS top 8%: very likely to be exploited; Remotely exploitable, no login, no user action; On your watchlist
Related CVEs
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