Microsoft Security Response Center guidance
Vendor revision: Oct 21, 2026Release Notes
Vendor-listed releases
- 6.6.157.1-1
Vulnerability intelligence
CVE-2026-90088. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
Vendor-listed releases
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop
rfcomm_apply_pn() accepts the MTU value from a remote PN (Parameter Negotiation) frame without checking for zero. When the remote peer sends an MTU of zero, d->mtu is set to 0.
This causes the sendmsg path to enter an infinite loop when fragmenting data, as each fragment has size == min_t(size_t, len, 0) == 0, so the remaining length never decreases. The infinite allocation of zero-length skbs exhausts all system memory.
Fix by clamping d->mtu to RFCOMM_DEFAULT_MTU when the negotiated value is zero, consistent with the initial value assigned in rfcomm_dlc_alloc().
Source: NVD