Answer in brief
CVE-2026-31773 records a High severity (CVSS 8.8) vulnerability in Bluetooth: SMP: derive legacy responder STK authentication from MITM state. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=fff3490f47810e2d34b91fb9e31103e923b11c2f <9a38659a3d06080715691bd3139f9c4b61f688e3 || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <667f44f1392df6482483756458c48670e579e9ff || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <929db734d12db41ca5f95424db4612397f1bd4a7 || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <b1c6a8e554a39b222c0879a288ea98e338fc4d77 || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <0afc846bd80073ffcd2b8040f2b2fafaea3d9f72 || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <061ee71ac6b03c9f8432fe49538c3682bfcf4cf3 || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <9a6d0db176f082685e0b6149700c0baf3ce2aa8b || >=fff3490f47810e2d34b91fb9e31103e923b11c2f <20756fec2f0108cb88e815941f1ffff88dc286fe || 14ec593d6bb050cf40a4ade2f9ac9ca050e0412c || >=3.15.5 <3.16 | 9a38659a3d06080715691bd3139f9c4b61f688e3, 667f44f1392df6482483756458c48670e579e9ff, 929db734d12db41ca5f95424db4612397f1bd4a7, b1c6a8e554a39b222c0879a288ea98e338fc4d77, 0afc846bd80073ffcd2b8040f2b2fafaea3d9f72, 061ee71ac6b03c9f8432fe49538c3682bfcf4cf3, 9a6d0db176f082685e0b6149700c0baf3ce2aa8b, 20756fec2f0108cb88e815941f1ffff88dc286fe, 3.16 |
| Linux/Linuxgeneric | 3.16 | Not reported |
Published upstream
May 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 16, 2026
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SMP: derive legacy responder STK authentication from MITM state The legacy responder path in smp_random() currently labels the stored STK as authenticated whenever pending_sec_level is BT_SECURITY_HIGH. That reflects what the local service requested, not what the pairing flow actually achieved. For Just Works/Confirm legacy pairing, SMP_FLAG_MITM_AUTH stays clear and the resulting STK should remain unauthenticated even if the local side requested HIGH security. Use the established MITM state when storing the responder STK so the key metadata matches the pairing result. This also keeps the legacy path aligned with the Secure Connections code, which already treats JUST_WORKS/JUST_CFM as unauthenticated.
Quoted source text, attributed separately from HOL analysis.