Red Hat Security Advisory: unbound security update
Red Hat has issued a security advisory for the unbound DNS resolver addressing a cache poisoning vulnerability (CVE-2026-44690) caused by insufficient RRSIG.Labels validation and premature cache writes. This vulnerability could allow an attacker to poison the DNS cache. The advisory also mentions a denial of service issue via malformed EDNS Report-Channel option (CVE-2026-55973). The update is rated as Important by Red Hat Product Security and affects Red Hat Enterprise Linux 8 versions. A security update is available to remediate these issues.
AI Analysis
Technical Summary
The unbound DNS resolver in Red Hat Enterprise Linux 8 contains a vulnerability (CVE-2026-44690) where insufficient validation of RRSIG.Labels and premature cache writes can lead to cache poisoning. This could allow an attacker to inject malicious DNS data into the resolver cache. Additionally, a denial of service vulnerability (CVE-2026-55973) exists via malformed EDNS Report-Channel options. Red Hat has released an update to fix these vulnerabilities in unbound packages for various architectures including x86_64, s390x, ppc64le, and aarch64. The advisory references updated packages and provides instructions for applying the fix.
Potential Impact
Successful exploitation of CVE-2026-44690 could allow an attacker to poison the DNS cache, potentially redirecting users to malicious sites or disrupting DNS resolution. CVE-2026-55973 could cause denial of service conditions via malformed DNS packets. The vulnerabilities affect Red Hat Enterprise Linux 8 systems running unbound, impacting DNS resolution integrity and availability.
Mitigation Recommendations
Red Hat has released an official security update that addresses these vulnerabilities. Users should apply the updated unbound packages as detailed in the Red Hat advisory RHSA-2026:55784 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are required beyond applying the official patch.
Red Hat Security Advisory: unbound security update
Description
Red Hat has issued a security advisory for the unbound DNS resolver addressing a cache poisoning vulnerability (CVE-2026-44690) caused by insufficient RRSIG.Labels validation and premature cache writes. This vulnerability could allow an attacker to poison the DNS cache. The advisory also mentions a denial of service issue via malformed EDNS Report-Channel option (CVE-2026-55973). The update is rated as Important by Red Hat Product Security and affects Red Hat Enterprise Linux 8 versions. A security update is available to remediate these issues.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The unbound DNS resolver in Red Hat Enterprise Linux 8 contains a vulnerability (CVE-2026-44690) where insufficient validation of RRSIG.Labels and premature cache writes can lead to cache poisoning. This could allow an attacker to inject malicious DNS data into the resolver cache. Additionally, a denial of service vulnerability (CVE-2026-55973) exists via malformed EDNS Report-Channel options. Red Hat has released an update to fix these vulnerabilities in unbound packages for various architectures including x86_64, s390x, ppc64le, and aarch64. The advisory references updated packages and provides instructions for applying the fix.
Potential Impact
Successful exploitation of CVE-2026-44690 could allow an attacker to poison the DNS cache, potentially redirecting users to malicious sites or disrupting DNS resolution. CVE-2026-55973 could cause denial of service conditions via malformed DNS packets. The vulnerabilities affect Red Hat Enterprise Linux 8 systems running unbound, impacting DNS resolution integrity and availability.
Mitigation Recommendations
Red Hat has released an official security update that addresses these vulnerabilities. Users should apply the updated unbound packages as detailed in the Red Hat advisory RHSA-2026:55784 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are required beyond applying the official patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:55784
- Cve Count
- 1
- State
- PUBLISHED
Threat ID: 6a838c43bf8831d539b4c142
Added to database: 08/17/2026, 22:33:39 UTC
Last enriched: 09/10/2026, 22:54:58 UTC
Last updated: 10/02/2026, 08:43:35 UTC
Views: 105
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