Remote kernel panic via unsigned length underflow
Published Oct 9, 2025 · Updated Oct 9, 2025
Out-of-bounds access in Linux 6.16 through 6.16.8 allows remote attackers to trigger a kernel panic via a crafted RxGK RESPONSE packet. In rxgk_yfs_decode_ticket(), subtracting a fixed 40-byte header from an untrusted ticket_len without first checking the minimum length wraps the unsigned result into an oversized extraction length. The unauthenticated path processes one UDP response during the challenge handshake, and the oversized length reaches skb_to_sgvec and trips BUG_ON(len).
Summary
What happened
Out-of-bounds access in Linux 6.16 through 6.16.8 allows remote attackers to trigger a kernel panic via a crafted RxGK RESPONSE packet. In rxgk_yfs_decode_ticket(), subtracting a fixed 40-byte header from an untrusted ticket_len without first checking the minimum length wraps the unsigned result into an oversized extraction length. The unauthenticated path processes one UDP response during the challenge handshake, and the oversized length reaches skb_to_sgvec and trips BUG_ON(len).
The record
- CVE
- CVE-2025-39962
- Published
- Oct 9, 2025
- Updated
- Oct 9, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-787, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 9, 2025CVE publishedPublication date reported by the CVE source.
- Oct 9, 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?
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- Affected versionversion=6.16
- Affected versionversion=9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <2429a197648178cd4dc930a9d87c13c547460564
- Affected versionversion=9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <71571e187106631a8127f2dde780f35caa358d33
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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