Vulmon
Amazon Linux 2 Security Advisory: ALAS-2024-2481
Advisory Release Date: 2024-02-29 10:03 Pacific
Advisory Updated Date: 2024-03-04 12:00 Pacific
Certain DNSSEC aspects of the DNS protocol (in RFC 4035 and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses when there is a zone with many DNSKEY and RRSIG records, aka the "KeyTrap" issue. The protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records. (CVE-2023-50387)
The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the "NSEC3" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations. (CVE-2023-50868)
Affected Packages:
unbound
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update unbound to update your system.
aarch64:
unbound-1.7.3-15.amzn2.0.7.aarch64
unbound-devel-1.7.3-15.amzn2.0.7.aarch64
unbound-libs-1.7.3-15.amzn2.0.7.aarch64
python2-unbound-1.7.3-15.amzn2.0.7.aarch64
python3-unbound-1.7.3-15.amzn2.0.7.aarch64
unbound-debuginfo-1.7.3-15.amzn2.0.7.aarch64
i686:
unbound-1.7.3-15.amzn2.0.7.i686
unbound-devel-1.7.3-15.amzn2.0.7.i686
unbound-libs-1.7.3-15.amzn2.0.7.i686
python2-unbound-1.7.3-15.amzn2.0.7.i686
python3-unbound-1.7.3-15.amzn2.0.7.i686
unbound-debuginfo-1.7.3-15.amzn2.0.7.i686
src:
unbound-1.7.3-15.amzn2.0.7.src
x86_64:
unbound-1.7.3-15.amzn2.0.7.x86_64
unbound-devel-1.7.3-15.amzn2.0.7.x86_64
unbound-libs-1.7.3-15.amzn2.0.7.x86_64
python2-unbound-1.7.3-15.amzn2.0.7.x86_64
python3-unbound-1.7.3-15.amzn2.0.7.x86_64
unbound-debuginfo-1.7.3-15.amzn2.0.7.x86_64