CVE-2026-59140 Memory corruption in Data::SortedSet::Shared
A local attacker with write access to the backing file can trigger out-of-bounds reads in Perl's Data::SortedSet::Shared, causing crashes or memory disclosure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-59140?
CVE-2026-59140 is a critical memory corruption vulnerability in EGOR Data::SortedSet::Shared, published on 21 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Data::SortedSet::Shared versions before 0.03 for Perl allow an out-of-bounds read via unvalidated node indices in the rank and min/max query paths.
The attach-time validator ss_validate_header bounds only the root index against the node pool (node_capacity). The order-statistics and min/max queries then follow children[], leftmost and rightmost node indices read raw from the mmap'd segment without bounding them against node_capacity. A full structural check (ss_validate_tree) exists but runs only via an explicit validate method, not on attach.
A local peer that can write the backing file can leave the header valid while poisoning the tree links, so the next rank, min or max query dereferences an out-of-bounds node index, reading adjacent memory or crashing the process.
Weakness: CWE-125
Which versions are affected by CVE-2026-59140?
How do I fix CVE-2026-59140?
No fix has been published for CVE-2026-59140 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-59140 being exploited?
There is no known exploitation of CVE-2026-59140 in the wild and no public exploit code.
Sources
Also known as GHSA-6qfv-wgp3-38c4.