CVE-2026-64613 Information disclosure in Data::Buffer::Shared
Local attackers can read shared memory data or overwrite arbitrary files due to world-readable permissions and missing symlink protection in the Perl library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-64613?
CVE-2026-64613 is a medium-severity vulnerability in EGOR Data::Buffer::Shared, published on 21 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW.
The segment is created in buf_generic.h with open(path, O_RDWR|O_CREAT|O_EXCL, 0666). O_EXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable), and O_NOFOLLOW is absent, so a symlink planted at the path is followed when the segment is attached.
A "Shared" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted symlink at the path redirects the open to another file.
Which versions are affected by CVE-2026-64613?
How do I fix CVE-2026-64613?
No fix has been published for CVE-2026-64613 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-64613 being exploited?
There is no known exploitation of CVE-2026-64613 in the wild and no public exploit code.
Sources
Also known as GHSA-pmmg-wc48-vjhq.