CVE-2021-21281: contiki-ng Classic Buffer Overflow
Vulnerability summary
CVE-2021-21281 is a critical (CVSS 9.8) Classic Buffer Overflow vulnerability in contiki-ng. EPSS estimates a 0.92% chance of exploitation in the next 30 days, higher than 59.8% of scored vulnerabilities.
Timeline
- 18-06-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
Contiki-NG is an open-source, cross-platform operating system for internet of things devices. A buffer overflow vulnerability exists in Contiki-NG versions prior to 4.6. After establishing a TCP socket using the tcp-socket library, it is possible for the remote end to send a packet with a data offset that is unvalidated. The problem has been patched in Contiki-NG 4.6. Users can apply the patch for this vulnerability out-of-band as a workaround.
CVSS metrics
3 scores · 2 sources · 2 versions- CVE.orgCNA7.0HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:HDiffers
EPSS trend
Probability
0.92%
Chance of exploitation in the next 30 days
Percentile
60%
Versus all other CVEs
30-day change
0.00 pp
From 0.92% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Contiki-ng1 product
- contiki-ng< 4.6
1 vendor · 1 product
References
2 links- github.com/contiki-ng/contiki-ng/security/advisories/GHSA-mc42-fqfr-h9fpX Refsource CONFIRMPatchThird Party Advisory