CVE-2026-7424

Description

Integer underflow in the DHCPv6 sub-option parser in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network actor to corrupt the device's IPv6 address assignment, DNS configuration, and lease times, and to cause a denial of service (permanent IP task freeze requiring hardware reset) by sending a single crafted DHCPv6 packet. The issue is present whenever DHCPv6 is enabled. To mitigate this issue, users should upgrade to version V4.2.6 or V4.4.1 or newer.

Is your site exposed to CVE-2026-7424?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

EPSS — Exploit Prediction

0.0002

Probability of exploitation

0.04%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-191 CWE-191

Affected Products

Vendor	Product	Versions
amazon	freertos-plus-tcp	4.0.0 — 4.2.6
amazon	freertos-plus-tcp	4.3.0 — 4.4.1

References

Advisories & Patches

https://aws.amazon.com/security/security-bulletins/2026-022-aws/ https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-wrhm-c99p-2p8g

Other References

https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6 https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1

Frequently Asked Questions

What is CVE-2026-7424? +

Integer underflow in the DHCPv6 sub-option parser in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network actor to corrupt the device's IPv6 address assignment, DNS configuration, and lease times, and to cause a denial of service (permanent IP task freeze requiring hardware reset) by sending a single crafted DHCPv6 packet. The issue is present whenever DHCPv6 is enabled. To mitigate this issue, users should upgrade to version V4.2.6 or V4.4.1 or newer. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-7424? +

CVE-2026-7424 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0002, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-7424? +

CVE-2026-7424 affects products from amazon, specifically: freertos-plus-tcp. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-7424? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-59368

An integer underflow vulnerability has been identified in Aicloud. An authenticated attacker may trigger this vulnerability by sending a crafted …

CVE-2025-65092

ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.1, 5.4.3, and 5.3.4, when the ESP32-P4 uses …

CVE-2026-43916

pam_authnft is a PAM session module binding nftables firewall rules to authenticated sessions via cgroupv2 inodes. Prior to 0.2.0-alpha, a …

CVE-2026-30803

Integer Underflow (Wrap or Wraparound) vulnerability in RTI Connext Micro (Core Libraries) allows Overread Buffers.This issue affects Connext Micro: from …

CVE-2024-0808 9.8

Integer underflow in WebUI in Google Chrome prior to 121.0.6167.85 allowed a remote attacker to potentially exploit heap corruption via …

CVE-2024-23313 9.8

An integer underflow vulnerability exists in the sopen_FAMOS_read functionality of The Biosig Project libbiosig 2.5.0 and Master Branch (ab0ee111). A …