Linux Kernel up to 6.12.111/6.18.54/7.2.8/7.3-rc4 Bluetooth RFCOMM rfcomm_recv_frame len return value

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.111/6.18.54/7.2.8/7.3-rc4. It has been declared as very critical. This vulnerability affects the function rfcomm_recv_frame of the component Bluetooth RFCOMM. The manipulation of the argument len results in return value. This vulnerability is identified as CVE-2026-98600. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.12.111/6.18.54/7.2.8/7.3-rc4. It has been classified as very critical. Affected is the function rfcomm_recv_frame of the component Bluetooth RFCOMM. The manipulation of the argument len with an unknown input leads to a return value vulnerability. CWE is classifying the issue as CWE-252. The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame() While rfcomm_recv_frame() verifies that skb->len is at least sizeof(*hdr) + 1 (4 bytes: 3-byte header + 1-byte FCS), an RFCOMM frame with an extended 2-byte length field (!__test_ea(hdr->len)) has a 4-byte header plus a 1-byte FCS (5 bytes minimum, sizeof(*hdr) + 2). When a 4-byte RFCOMM frame with EA == 0 arrives: 1. The initial skb->len < sizeof(*hdr) + 1 check passes (4 < 4 is false). 2. Trimming the FCS byte decrements skb->len to 3. 3. If __check_fcs() succeeds, skb_pull(skb, 4) fails (4 > 3) and returns NULL without advancing skb->data. 4. Because the return value of skb_pull() is ignored, the un-pulled 3-byte struct rfcomm_hdr remains at skb->data and is either queued as application payload via rfcomm_recv_data() or parsed as a multiplexer control command via rfcomm_recv_mcc() on DLCI 0. Fix this by extending the length check in rfcomm_recv_frame() to also require skb->len >= sizeof(*hdr) + 2 when !__test_ea(hdr->len).

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-98600 since 09/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 10/18/2026).

Upgrading to version 6.12.112, 6.18.55, 7.2.9 or 7.3-rc5 eliminates this vulnerability. Applying the patch 76876fd26569302d26d91cbe8b75fa8e66cf8969/97711b964877242933484989224a3c4c5d88a5ee/7a1781a2f3a9667b3065d402d1f11986a2363e08/c25587fa26761e623198b4f47151fe79d09ccde6/71ccacde407b7d8f0ef48974a0d2524602fd5c44/be00deee60044ffa820f9436415caeb665b2cda0/9240fc1f2cde5331c61608da21b00394602ca762/6d91041bb38b97e2feb625123cc0529d7b83a0e1 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
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: Return value
CWE: CWE-252 / CWE-253
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 6.12.112/6.18.55/7.2.9/7.3-rc5
Patch: 76876fd26569302d26d91cbe8b75fa8e66cf8969/97711b964877242933484989224a3c4c5d88a5ee/7a1781a2f3a9667b3065d402d1f11986a2363e08/c25587fa26761e623198b4f47151fe79d09ccde6/71ccacde407b7d8f0ef48974a0d2524602fd5c44/be00deee60044ffa820f9436415caeb665b2cda0/9240fc1f2cde5331c61608da21b00394602ca762/6d91041bb38b97e2feb625123cc0529d7b83a0e1

Timelineinfo

09/25/2026 CVE reserved
10/18/2026 +23 days Advisory disclosed
10/18/2026 +0 days VulDB entry created
10/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98600 (🔒)
GCVE (CVE): GCVE-0-2026-98600
GCVE (VulDB): GCVE-100-422106

Entryinfo

Created: 10/18/2026 20:22
Changes: 10/18/2026 20:22 (60)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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