High severity · published Oct 16, 2026
CVE-2026-102551
Improper verification of the source of a communication channel in FreeRTOS-Plus-TCP Router Advertisement handling
7.7
CVSS
0.3%
EPSS
No
On KEV
Description
Improper verification of the source of a communication channel in the IPv6 Router Advertisement handler in Amazon FreeRTOS-Plus-TCP before V4.4.2 might allow a remote third-party to influence an endpoint's IPv6 default gateway, on-link prefix, and address configuration via a crafted Router Advertisement.
To remediate this issue, users should upgrade to version V4.4.2.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRTOS-Plus-TCP · FreeRTOS
through 4.4.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-102551
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-102551
aws.amazon.com
https://aws.amazon.com/security/security-bulletins/2026-139-aws/
github.com
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.2
github.com
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-pjq5-fqrr-g6pv
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