zephyrproject-rtos Zephyr up to 4.3 DNS dns_unpack_name out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.8$0-$5k0.00

Summaryinfo

A vulnerability has been found in zephyrproject-rtos Zephyr up to 4.3 and classified as critical. The affected element is the function dns_unpack_name of the component DNS Handler. Performing a manipulation results in out-of-bounds write. This vulnerability is identified as CVE-2026-1678. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in zephyrproject-rtos Zephyr up to 4.3. It has been classified as critical. This affects the function dns_unpack_name of the component DNS Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

dns_unpack_name() caches the buffer tailroom once and reuses it while appending DNS labels. As the buffer grows, the cached size becomes incorrect, and the final null terminator can be written past the buffer. With assertions disabled (default), a malicious DNS response can trigger an out-of-bounds write when CONFIG_DNS_RESOLVER is enabled.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-1678 since 01/30/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/10/2026).

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: 8.8
VulDB Meta Temp Score: 8.8

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

NVD Base Score: 9.8
NVD Vector: 🔒

CNA Base Score: 9.4
CNA Vector (zephyr): 🔒

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
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

01/30/2026 CVE reserved
03/05/2026 +34 days Advisory disclosed
03/05/2026 +0 days VulDB entry created
03/10/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-1678 (🔒)
GCVE (CVE): GCVE-0-2026-1678
GCVE (VulDB): GCVE-100-348981

Entryinfo

Created: 03/05/2026 07:53
Updated: 03/10/2026 12:02
Changes: 03/05/2026 07:53 (64), 03/07/2026 20:23 (1), 03/10/2026 12:02 (11)
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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