Linux Kernel up to 7.1.8 Thunderbolt tb_drom_parse_entry_port dual_link_port_nr out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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7.8$0-$5k2.17

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.1.8 and classified as very critical. This impacts the function tb_drom_parse_entry_port of the component Thunderbolt. Such manipulation of the argument dual_link_port_nr leads to out-of-bounds. This vulnerability is referenced as CVE-2026-74585. The attack can only be performed from a local environment. No exploit is available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.1.8. It has been rated as very critical. Affected by this issue is the function tb_drom_parse_entry_port of the component Thunderbolt. The manipulation of the argument dual_link_port_nr with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: thunderbolt: Bound the DROM dual link port number before indexing sw->ports tb_drom_parse_entry_port() validates the device-supplied header->index against sw->config.max_port_number before indexing sw->ports[], but the sibling field entry->dual_link_port_nr -- a 6-bit value also read from the DROM -- indexes the same array with no such check. A malicious or malformed Thunderbolt device can set dual_link_port_nr beyond the allocated sw->ports[] (max_port_number + 1 entries), producing an out-of-bounds tb_port pointer that is stored and later dereferenced. Reject a port entry whose dual_link_port_nr exceeds max_port_number, the same bound already applied to header->index.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2026-74585 since 08/15/2026. The exploitation is known to be easy. Local access is required to approach this attack. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 08/22/2026).

Upgrading to version 5.10.265, 5.15.216, 6.1.183, 6.6.152, 6.12.104, 6.18.45 or 7.1.9 eliminates this vulnerability. Applying the patch 6c892ed9f4129ae40ef0f92e1bb31aa0b0ddc72c/3d3c212b70633332ab71672aa2bc6af257d2ec83/b98e1e28bd95b0fa33164eec1e763d26c7058b39/50f0c8dd8c3390f851cfb97ca13116f9ee6469d1/f28066057134aa9294caa597b670daf505ad9dce/40d2ffb74094cf36edbe05855566a4c58b6ce808/f32c3a9a77cfb50934a60b05d5407649af062535/d6764992f17b23d91ff93ce905ab53c2aa7191f0 is able to eliminate this problem.

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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: 8.2
VulDB Meta Temp Score: 7.8

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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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: Partially
Local: Yes
Remote: Partially

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 5.10.265/5.15.216/6.1.183/6.6.152/6.12.104/6.18.45/7.1.9
Patch: 6c892ed9f4129ae40ef0f92e1bb31aa0b0ddc72c/3d3c212b70633332ab71672aa2bc6af257d2ec83/b98e1e28bd95b0fa33164eec1e763d26c7058b39/50f0c8dd8c3390f851cfb97ca13116f9ee6469d1/f28066057134aa9294caa597b670daf505ad9dce/40d2ffb74094cf36edbe05855566a4c58b6ce808/f32c3a9a77cfb50934a60b05d5407649af062535/d6764992f17b23d91ff93ce905ab53c2aa7191f0

Timelineinfo

08/15/2026 CVE reserved
08/22/2026 +7 days Advisory disclosed
08/22/2026 +0 days VulDB entry created
08/22/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74585 (🔒)
GCVE (CVE): GCVE-0-2026-74585
GCVE (VulDB): GCVE-100-394370

Entryinfo

Created: 08/22/2026 17:53
Changes: 08/22/2026 17:53 (60)
Complete: 🔍
Cache ID: 216::103

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