zephyrproject-rtos Zephyr up to 4.2 pb_adv.c gen_prov_start buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in zephyrproject-rtos Zephyr up to 4.2. Impacted is the function gen_prov_start of the file pb_adv.c. Executing a manipulation can lead to buffer overflow. This vulnerability is registered as CVE-2025-9558. The attack requires access to the local network. No exploit is available.

Detailsinfo

A vulnerability has been found in zephyrproject-rtos Zephyr up to 4.2 and classified as critical. This vulnerability affects the function gen_prov_start of the file pb_adv.c. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

There is a potential OOB Write vulnerability in the gen_prov_start function in pb_adv.c. The full length of the received data is copied into the link.rx.buf receiver buffer without any validation on the data size.

The advisory is shared for download at github.com. This vulnerability was named CVE-2025-9558 since 08/27/2025. The exploitation appears to be easy. The attack can only be initiated within the local network. 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 11/27/2025).

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-2025-199712). Once again VulDB remains the best source for vulnerability data.

Productinfo

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Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.9

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

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: Buffer overflow
CWE: CWE-120 / 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

08/27/2025 CVE reserved
11/26/2025 +91 days Advisory disclosed
11/26/2025 +0 days VulDB entry created
11/27/2025 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2025-9558 (🔒)
GCVE (CVE): GCVE-0-2025-9558
GCVE (VulDB): GCVE-100-333580
EUVD: 🔒

Entryinfo

Created: 11/26/2025 06:54
Updated: 11/27/2025 13:41
Changes: 11/26/2025 06:54 (64), 11/26/2025 16:04 (1), 11/27/2025 13:41 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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