Amazon Web Services (AWS) FreeRTOS through 1.3.1, FreeRTOS up to V10.0.1 (with FreeRTOS+TCP), and WITTENSTEIN WHIS Connect middleware TCP/I…

published 2018-12-06 7y ago modified 2026-06-17 4mo ago also EUVD-2018-8335

cvss: 8.1; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 4.4%; EPSS 4.4% chance of exploitation in 30 days, percentile 91%
public exploits: 0; none known

Amazon Web Services (AWS) FreeRTOS through 1.3.1, FreeRTOS up to V10.0.1 (with FreeRTOS+TCP), and WITTENSTEIN WHIS Connect middleware TCP/IP component allow remote attackers to leak information or execute arbitrary code because of a Buffer Overflow during generation of a protocol checksum in usGenerateProtocolChecksum and prvProcessIPPacket.

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Exploit prediction

4.44% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

blog.zimperium.com https://blog.zimperium.com/freertos-tcpip-stack-vulnerabilities-details/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	8.1	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P

References

blog.zimperium.com /freertos-tcpip-stack-vulnerabilities-details/
exploit, third-party-advisory
github.com /aws/amazon-freertos/blob/v1.3.2/CHANGELOG.md
release-notes, third-party-advisory
blog.zimperium.com /freertos-tcpip-stack-vulnerabilities-put-wide-range-devices-risk-compromise-smart-homes-critical-infrastructu
third-party-advisory

Sources

CVE List CVE-2018-16526
NVD CVE-2018-16526

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