zephyrproject-rtos Zephyr up to 4.1 bt_conn_tx_processor write-what-where condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.8$0-$5k0.00

Summaryinfo

A vulnerability was found in zephyrproject-rtos Zephyr up to 4.1. It has been classified as critical. This vulnerability affects the function bt_conn_tx_processor. Performing a manipulation results in write-what-where condition. This vulnerability is reported as CVE-2025-7403. The attacker must have access to the local network to execute the attack. No exploit exists.

Detailsinfo

A vulnerability was found in zephyrproject-rtos Zephyr up to 4.1. It has been classified as critical. This affects the function bt_conn_tx_processor. The manipulation with an unknown input leads to a write-what-where condition vulnerability. CWE is classifying the issue as CWE-123. Any condition where the attacker has the ability to write an arbitrary value to an arbitrary location, often as the result of a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in a write-before-zero. The written 4 bytes are attacker-controlled, enabling precise memory corruption.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2025-7403 since 07/10/2025. The exploitability is told to be easy. Access to the local network is required for this attack. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/29/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-30240). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.8

VulDB Base Score: 6.3
VulDB Temp Score: 6.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔒

CNA Base Score: 7.6
CNA Vector (zephyr): 🔒

CVSSv2info

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

Exploitinginfo

Class: Write-what-where condition
CWE: CWE-123 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/10/2025 CVE reserved
09/19/2025 +71 days Advisory disclosed
09/19/2025 +0 days VulDB entry created
10/29/2025 +40 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2025-7403 (🔒)
GCVE (CVE): GCVE-0-2025-7403
GCVE (VulDB): GCVE-100-324987
EUVD: 🔒

Entryinfo

Created: 09/19/2025 07:50
Updated: 10/29/2025 21:12
Changes: 09/19/2025 07:50 (62), 09/19/2025 08:30 (1), 10/29/2025 21:12 (11)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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