CVE-2025-5688

Out of Bounds Write in FreeRTOS-Plus-TCP

We have identified a buffer overflow issue allowing out-of-bounds write when processing LLMNR or mDNS queries with very long DNS names. This issue only affects systems using Buffer Allocation Scheme 1 with LLMNR or mDNS enabled. Users should upgrade to the latest version and ensure any forked or derivative code is patched to incorporate the new fixes.

Affected

Amazon · FreeRTOS

CVSS v4.0 CNA

7.5 HIGHCVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS

0.35% chance of exploitation in the next 30 days, 27th percentile

Published

2025-06-04

Updated

2025-10-14

Proof-of-concept exploits (1)

• mbanyamer/CVE-2025-5688-FreeRTOS-Plus-TCP-Out-of-Bounds-Write0★ · 2026-02-26

References

• CVE Record
• NVD entry

Related

• CVE-2019-7711
• CVE-2021-41579
• CVE-2023-31059
• CVE-2025-24076
• CVE-2025-24813
• CVE-2025-30397