CVE-2026-77955

Name
CVE-2026-77955
Description
In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD configured zones (zonemd-check: yes) which are located below (but not at) a trust anchor allow for an attack window where (tampered with) zone contents are served (or stored to disk) prior to the ZONEMD integrity check. This is caused by the needed DS/DNSKEY asynchronous resolution that needs to happen before the ZONEMD check completes. If a zonefile is written to disk (zonefile: option) while the ZONEMD check failed, the tampered data are reloaded on startup and available until ZONEMD verification concludes again. If verification fails, the data is not served any more but still persists on disk for future reloads.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
Patch https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-77955.txt

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:* unbound >= 1.13.2 < 1.26.1

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
unbound edge-main 1.26.1-r0 Jakub Jirutka <jakub@jirutka.cz> fixed
unbound edge-main 1.26.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.25.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.25.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.25.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.24.2-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.24.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.24.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.24.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.23.1-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.23.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.23.0-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.23.0-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.23.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.22.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.21.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.20.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.19.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.19.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.16.3-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound edge-main 1.16.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.24-main 1.25.2-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.24-main 1.25.2-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.24-main 1.25.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.24-main 1.25.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.23-main 1.25.2-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.23-main 1.25.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.23-main 1.24.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.22-main 1.25.2-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.22-main 1.25.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.22-main 1.23.1-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.22-main 1.23.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.22-main 1.23.0-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.22-main 1.21.1-r0 None possibly vulnerable
unbound 3.22-main 1.20.0-r0 None possibly vulnerable
unbound 3.22-main 1.19.2-r0 None possibly vulnerable
unbound 3.22-main 1.19.1-r0 None possibly vulnerable
unbound 3.22-main 1.16.3-r0 None possibly vulnerable
unbound 3.22-main 1.16.2-r0 None possibly vulnerable
unbound 3.21-main 1.22.0-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.21-main 1.22.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.21-main 1.21.1-r0 None possibly vulnerable
unbound 3.21-main 1.20.0-r0 None possibly vulnerable
unbound 3.21-main 1.19.2-r0 None possibly vulnerable
unbound 3.21-main 1.19.1-r0 None possibly vulnerable
unbound 3.21-main 1.16.3-r0 None possibly vulnerable
unbound 3.21-main 1.16.2-r0 None possibly vulnerable
unbound 3.20-main 1.20.0-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.20-main 1.20.0-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.20-main 1.20.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.20-main 1.19.2-r0 None possibly vulnerable
unbound 3.20-main 1.19.1-r0 None possibly vulnerable
unbound 3.20-main 1.16.3-r0 None possibly vulnerable
unbound 3.20-main 1.16.2-r0 None possibly vulnerable
unbound 3.19-main 1.20.0-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.19-main 1.20.0-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.19-main 1.20.0-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.19-main 1.19.2-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.19-main 1.19.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
unbound 3.19-main 1.16.3-r0 None possibly vulnerable
unbound 3.19-main 1.16.2-r0 None possibly vulnerable