Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update

CVE-2026-80212 is a denial of service vulnerability in the Ruby resolv gem, affecting Red Hat Hardened Images and Ruby 4.0 packages. The flaw arises from uncontrolled memory growth when processing specially crafted DNS responses, which can cause the affected software to crash or become unresponsive. Red Hat has released security updates for multiple ruby4.0-related RPM packages including ruby4.0-4.0.6-37.3.hum1 and associated gems to remediate this issue. There are no reports of exploitation in the wild at this time.

Successful exploitation of this vulnerability can cause denial of service by exhausting memory resources due to uncontrolled memory growth when handling malicious DNS responses. This can disrupt services relying on the affected Ruby packages, potentially causing application crashes or system instability. No evidence of active exploitation has been reported.

Red Hat has released updated RPM packages for ruby4.0 and related gems that address this vulnerability. Users of Red Hat Hardened Images and Ruby 4.0 packages should apply the security updates as provided in Red Hat Advisory RHSA-2026:62563. No additional mitigation steps are indicated by the vendor.