dns: memory‑safety issue in the DNS name parser (zephyrproject-rtos Zephyr)

CVE-2026-1678
CRITICAL 9.4

At a glance

Source
NVD
EPSS
EPSS 0.44 % · percentile 38 ()
State
PUBLISHED
Published
Updated
Assigner
zephyr
NVD status
Analyzed

Description

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.

Weaknesses (CWE)

  • CWE-787 — Out-of-bounds Write

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.4CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:Hzephyr
CVSS 3.1CRITICAL 9.4CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:HNVD · vulnerabilities@zephyrproject.org (Secondary)
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HNVD · nvd@nist.gov (Primary)

European references

Affected configurations (NVD CPE)

Affected products

ProductVersions
zephyrproject-rtos · Zephyraffected * < 3.7.2 ; affected 4.0.0 < 4.2.2 ; affected 4.3.0 < 4.3.1

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD