Medium 6.5Published Apr 29, 2026

CVE-2026-7422MAC Address Validation Bypass in FreeRTOS-Plus-TCP IPv4 and IPv6 Packet Processing

Updated under an hour ago (Oct 26, 2026, 8:40 AM ET)

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It affects AWS FreeRTOS-Plus-TCP and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for AWS FreeRTOS-Plus-TCP

Exploited in the last 30 days

Insufficient packet validation in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to bypass all checksum and minimum-size validation by spoofing the Ethernet source MAC address to match one of the device's own registered endpoints, because the loopback detection mechanism skips all input validation for packets whose source MAC matches a local endpoint. To mitigate this issue, users should upgrade to the fixed version when available.

CVSS: 6.5 MEDIUM (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness (CWE): CWE-290
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: AMZN
NVD analysis: Analyzed
Record last updated: Apr 29, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

AWS FreeRTOS-Plus-TCP aws:freertos_plus_tcp (from the name)	from 4.0.0 before 4.2.6; from 4.3.0 before 4.4.1; 4.2.6 not affected; 4.4.1 not affected	CNA record
amazon freertos-plus-tcp amazon:freertos-plus-tcp	from 4.0.0 before 4.2.6; from 4.3.0 before 4.4.1	NVD

References

https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1patch, release-notes
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6patch, release-notes
https://aws.amazon.com/security/security-bulletins/2026-021-aws/vendor-advisory
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-jpw4-6h59-62w9third-party-advisory, patch, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.