Red Hat Security Advisory: glibc security update
The glibc packages provide the standard C libraries (libc), POSIX thread libraries (libpthread), standard math libraries (libm), and the name service cache daemon (nscd) used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly. Security Fix(es): * glibc: glibc: Incorrect DNS response parsing via crafted DNS server response (CVE-2026-4437) * glibc: glibc: Invalid DNS hostname returned via gethostbyaddr functions (CVE-2026-4438) * glibc: glibc: Denial of Service via iconv() function with specific character sets (CVE-2026-4046) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
This Red Hat security advisory addresses three vulnerabilities in the glibc packages used by Red Hat Enterprise Linux 9 and related variants. The vulnerabilities include incorrect DNS response parsing from crafted DNS server responses (CVE-2026-4437), invalid DNS hostnames returned by gethostbyaddr functions (CVE-2026-4438), and a denial of service condition triggered via the iconv() function when processing specific character sets (CVE-2026-4046). These issues affect core system libraries essential for DNS resolution and character set conversions. The advisory provides updated glibc packages to remediate these vulnerabilities.
Potential Impact
The vulnerabilities could lead to incorrect DNS data processing, potentially causing applications to receive invalid DNS hostnames or fail to parse DNS responses correctly. The denial of service vulnerability could cause system or application crashes when processing certain character sets via iconv(). These issues impact system stability and reliability but do not have confirmed exploits in the wild.
Mitigation Recommendations
Red Hat has released updated glibc packages for Red Hat Enterprise Linux 9 and related variants that address these vulnerabilities. Users should apply the provided security updates as detailed in the Red Hat advisory RHSA-2026:20597. No additional mitigation steps are indicated beyond applying the official patches.
Red Hat Security Advisory: glibc security update
Description
The glibc packages provide the standard C libraries (libc), POSIX thread libraries (libpthread), standard math libraries (libm), and the name service cache daemon (nscd) used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly. Security Fix(es): * glibc: glibc: Incorrect DNS response parsing via crafted DNS server response (CVE-2026-4437) * glibc: glibc: Invalid DNS hostname returned via gethostbyaddr functions (CVE-2026-4438) * glibc: glibc: Denial of Service via iconv() function with specific character sets (CVE-2026-4046) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory addresses three vulnerabilities in the glibc packages used by Red Hat Enterprise Linux 9 and related variants. The vulnerabilities include incorrect DNS response parsing from crafted DNS server responses (CVE-2026-4437), invalid DNS hostnames returned by gethostbyaddr functions (CVE-2026-4438), and a denial of service condition triggered via the iconv() function when processing specific character sets (CVE-2026-4046). These issues affect core system libraries essential for DNS resolution and character set conversions. The advisory provides updated glibc packages to remediate these vulnerabilities.
Potential Impact
The vulnerabilities could lead to incorrect DNS data processing, potentially causing applications to receive invalid DNS hostnames or fail to parse DNS responses correctly. The denial of service vulnerability could cause system or application crashes when processing certain character sets via iconv(). These issues impact system stability and reliability but do not have confirmed exploits in the wild.
Mitigation Recommendations
Red Hat has released updated glibc packages for Red Hat Enterprise Linux 9 and related variants that address these vulnerabilities. Users should apply the provided security updates as detailed in the Red Hat advisory RHSA-2026:20597. No additional mitigation steps are indicated beyond applying the official patches.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:20597
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-4437","CVE-2026-4438"]
- State
- PUBLISHED
Threat ID: 6a160976e29bf47b50641d61
Added to database: 05/26/2026, 20:58:30 UTC
Last enriched: 08/16/2026, 18:32:04 UTC
Last updated: 09/11/2026, 22:06:33 UTC
Views: 201
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