Memory corruption via oversized LLMNR or mDNS names
Published Jun 4, 2025 · Updated Oct 14, 2025
Out-of-bounds write in FreeRTOS-Plus-TCP 2.3.4 through 4.3.1 allows attackers to corrupt memory via long LLMNR or mDNS names. The LLMNR and mDNS query handler places data derived from an oversized DNS name into a fixed-size Scheme 1 network buffer without adequate bounds checks. Reachability requires Buffer Allocation Scheme 1 and an enabled LLMNR or mDNS service; the resulting overwrite can corrupt device memory.
Summary
What happened
Out-of-bounds write in FreeRTOS-Plus-TCP 2.3.4 through 4.3.1 allows attackers to corrupt memory via long LLMNR or mDNS names. The LLMNR and mDNS query handler places data derived from an oversized DNS name into a fixed-size Scheme 1 network buffer without adequate bounds checks. Reachability requires Buffer Allocation Scheme 1 and an enabled LLMNR or mDNS service; the resulting overwrite can corrupt device memory.
The record
- CVE
- CVE-2025-5688
- Published
- Jun 4, 2025
- Updated
- Oct 14, 2025
- Vendor
- Amazon Web Services
- Product
- FreeRTOS
- Classifications
- CWE-787, T1499.004
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 4, 2025CVE publishedPublication date reported by the CVE source.
- Oct 14, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.3.4 <4.3.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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