High severity · published Jun 4, 2025
CVE-2025-5688
Out of Bounds Write in FreeRTOS-Plus-TCP
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRTOS · Amazon
2.3.4 before 4.3.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-5688
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-5688
aws.amazon.com
https://aws.amazon.com/security/security-bulletins/AWS-2025-012/
github.com
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.3.2
github.com
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-5x4f-fvv8-wr65
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