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Critical ALAS2-2026-3928 1 CVE

Critical: unbound security update (Amazon Linux 2)

Published Sep 17, 2026 · Updated Sep 17, 2026

Ecosystem: Amazon Linux

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2026-81642: 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.

Fixed packages 6

ReleasePackageFixed in
Amazon Linux · 2 python2-unbound 0:1.7.3-15.amzn2.0.16
Amazon Linux · 2 python3-unbound 0:1.7.3-15.amzn2.0.16
Amazon Linux · 2 unbound 0:1.7.3-15.amzn2.0.16
Amazon Linux · 2 unbound-debuginfo 0:1.7.3-15.amzn2.0.16
Amazon Linux · 2 unbound-devel 0:1.7.3-15.amzn2.0.16
Amazon Linux · 2 unbound-libs 0:1.7.3-15.amzn2.0.16

Vulnerabilities 1

  • Critical 9.1
    CVE-2026-81642 Public exploit

    Heap buffer overflow and possible Remote Code Execution when digesting DNSKEY

    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…

    NLnet Labs Unbound unbound unbound Debian Ubuntu Azure Linux Alpine

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-81642.html