CVE-2026-65064 EGOR CVE debrief

Who should care

Users of Data::HashMap::Shared versions before 0.14 for Perl should be aware of this vulnerability and take steps to mitigate it. This includes upgrading to version 0.14 or later, and implementing additional security measures such as restricting access to the shared directory and monitoring for potential attacks.

Technical summary

The vulnerability is caused by the creation of a world-readable mmap backing file in shm_generic.h with open(path, O_RDWR | O_CREAT | O_CLOEXEC, 0666). The mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable). O_NOFOLLOW is absent, so a symlink planted at the path is followed, and O_EXCL is absent, so the open silently uses a pre-planted file instead of failing. This allows a local attacker to read the IPC payloads stored in the world-readable segment and potentially win a pre-creation race or redirect the open.

Defensive priority

High

Recommended defensive actions

• Upgrade to Data::HashMap::Shared version 0.14 or later
• Restrict access to the shared directory
• Implement additional security measures such as monitoring and exception tracking
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record was published on 2026-07-21T20:17:05.430Z and was last modified on 2026-07-22T16:21:53.517Z. The NVD entry is currently Deferred. Evidence is limited to public sources and may not reflect the full scope or impact of this vulnerability. Defenders should verify affected deployments and review official advisories for specific guidance.

Official resources