dns: memory‑safety issue in the DNS name parser

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-1678
StatePUBLISHED
Assignerzephyr
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-03-05 07:16:11 UTC
Updated2026-10-15 23:17:36 UTC
Descriptiondns_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.

Risk And Classification

Primary CVSS: v3.1 9.8 CRITICAL from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.003900000 probability, percentile 0.315210000 (date 2026-10-15)

Problem Types: CWE-787 | CWE-787 Out-of-bounds Write

VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary9.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
3.1[email protected]Secondary9.4CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H
3.1CNACVSS9.4CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Zephyrproject Zephyr All All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Zephyrproject-rtos Zephyr affected * 3.7.2 git Not specified
CNA Zephyrproject-rtos Zephyr affected 4.0.0 4.2.2 git Not specified
CNA Zephyrproject-rtos Zephyr affected 4.3.0 4.3.1 git Not specified

References

ReferenceSourceLinkTags
github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-... 134c704f-9b21-4f2e-91b3-4a467353bcc0 github.com Exploit, Patch, Vendor Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report