Linux Kernel up to 6.12.110/6.18.52 Bluetooth RFCOMM rfcomm_recv_frame out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k0.00+

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.110/6.18.52 and classified as very critical. The impacted element is the function rfcomm_recv_frame of the component Bluetooth RFCOMM. Executing a manipulation can lead to out-of-bounds. The identification of this vulnerability is CVE-2026-93783. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.12.110/6.18.52 and classified as very critical. This vulnerability affects the function rfcomm_recv_frame of the component Bluetooth RFCOMM. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: validate skb length in rfcomm_recv_frame rfcomm_recv_frame() casts skb->data to struct rfcomm_hdr and dereferences hdr->addr and hdr->ctrl without validating skb->len first. A truncated frame with skb->len less than the minimum header size causes an out-of-bounds read of uninitialized memory. Additionally, a zero-length frame causes skb->len-- to underflow to UINT_MAX, making skb_tail_pointer() read far past the buffer. Commit 23882b828c3c ("Bluetooth: RFCOMM: validate skb length in MCC handlers") fixed the same class of missing-length-check bugs in the MCC sub-handlers, but the top-level rfcomm_recv_frame() was left unfixed. KMSAN reports: BUG: KMSAN: uninit-value in rfcomm_run ... Uninit was created at: __alloc_skb+0x474/0xb60 vhci_write+0xe9/0x870 Fix this by rejecting frames smaller than sizeof(struct rfcomm_hdr) + 1 (the minimum frame must have a 3-byte header and a 1-byte FCS).

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-93783 since 09/18/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/24/2026).

Upgrading to version 6.12.111 or 6.18.53 eliminates this vulnerability. Applying the patch 67dc3b40fae71b6b11c71e7ff69bac0758818c05/bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51/b230e5bf501c5edaf2eb0991cb862ac142031d4b is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.12.111/6.18.53
Patch: 67dc3b40fae71b6b11c71e7ff69bac0758818c05/bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51/b230e5bf501c5edaf2eb0991cb862ac142031d4b

Timelineinfo

09/18/2026 CVE reserved
09/24/2026 +6 days Advisory disclosed
09/24/2026 +0 days VulDB entry created
09/24/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-93783 (🔒)
GCVE (CVE): GCVE-0-2026-93783
GCVE (VulDB): GCVE-100-409504

Entryinfo

Created: 09/24/2026 18:50
Changes: 09/24/2026 18:50 (59)
Complete: 🔍
Cache ID: 216::103

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