Amazon Linux 2 (EOS) Security Advisory: ALAS2UNBOUND-1.17-2026-010
Advisory Released Date: 2026-09-17
Advisory Updated Date: 2026-09-17
In NLnet Labs Unbound up to and including 1.26.0, a vulnerability was found in the DNSSEC validator that enables denial of service and possible remote code execution as a result of digesting DNSKEYs. A DNSKEY with an owner compression pointer to its own RDATA can overflow the digest buffer. Remote code execution is possible through attacker controlled data. An adversary can exploit the vulnerability by controlling a malicious zone and querying a vulnerable Unbound. (CVE-2026-81642)
Affected Packages:
unbound
Note:
This advisory is applicable to Amazon Linux 2 - Unbound-1.17 Extra. Visit this page to learn more about Amazon Linux 2 (AL2) Extras and this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update unbound or yum update --advisory ALAS2UNBOUND-1.17-2026-010 to update your system.
aarch64:
unbound-1.17.0-2.amzn2.0.13.aarch64
unbound-devel-1.17.0-2.amzn2.0.13.aarch64
unbound-libs-1.17.0-2.amzn2.0.13.aarch64
unbound-anchor-1.17.0-2.amzn2.0.13.aarch64
unbound-utils-1.17.0-2.amzn2.0.13.aarch64
python2-unbound-1.17.0-2.amzn2.0.13.aarch64
python3-unbound-1.17.0-2.amzn2.0.13.aarch64
unbound-debuginfo-1.17.0-2.amzn2.0.13.aarch64
src:
unbound-1.17.0-2.amzn2.0.13.src
x86_64:
unbound-1.17.0-2.amzn2.0.13.x86_64
unbound-devel-1.17.0-2.amzn2.0.13.x86_64
unbound-libs-1.17.0-2.amzn2.0.13.x86_64
unbound-anchor-1.17.0-2.amzn2.0.13.x86_64
unbound-utils-1.17.0-2.amzn2.0.13.x86_64
python2-unbound-1.17.0-2.amzn2.0.13.x86_64
python3-unbound-1.17.0-2.amzn2.0.13.x86_64
unbound-debuginfo-1.17.0-2.amzn2.0.13.x86_64