zephyrproject-rtos Zephyr up to 4.2 ICMP Type 128 type confusion

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 was found in zephyrproject-rtos Zephyr up to 4.2. It has been classified as critical. Affected by this vulnerability is an unknown functionality of the component ICMP Type 128 Handler. This manipulation causes type confusion. This vulnerability appears as CVE-2025-12899. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability has been found in zephyrproject-rtos Zephyr up to 4.2 and classified as critical. Affected by this vulnerability is an unknown code block of the component ICMP Type 128 Handler. The manipulation with an unknown input leads to a type confusion vulnerability. The CWE definition for the vulnerability is CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A flaw in Zephyr’s network stack allows an IPv4 packet containing ICMP type 128 to be misclassified as an ICMPv6 Echo Request. This results in an out-of-bounds memory read and creates a potential information-leak vulnerability in the networking subsystem.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-12899 since 11/07/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 02/05/2026).

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

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

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: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (zephyr): 🔒

CVSSv2info

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

Exploitinginfo

Class: Type confusion
CWE: CWE-843
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

11/07/2025 CVE reserved
01/30/2026 +84 days Advisory disclosed
01/30/2026 +0 days VulDB entry created
02/05/2026 +6 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-c2vg-hj83-c2vg
Status: Confirmed

CVE: CVE-2025-12899 (🔒)
GCVE (CVE): GCVE-0-2025-12899
GCVE (VulDB): GCVE-100-343453

Entryinfo

Created: 01/30/2026 08:07
Updated: 02/05/2026 06:07
Changes: 01/30/2026 08:07 (63), 02/05/2026 06:07 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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