# CVE-2026-59146: Memory corruption in Data::SpatialHash::Shared

> A local attacker with file write access can trigger out-of-bounds reads and writes in the Perl Data::SpatialHash::Shared library, leading to memory corruption or crashes.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 21 Jul 2026
- **Updated:** 22 Jul 2026
- **Also known as:** GHSA-p5xm-h38r-4xmg

## What is CVE-2026-59146?

CVE-2026-59146 is a high-severity memory corruption vulnerability in EGOR Data::SpatialHash::Shared, published on 21 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

Data::SpatialHash::Shared versions before 0.02 for Perl allow out-of-bounds reads and writes via unvalidated bucket, link and free-list indices in sph_walk_cell and sph_alloc_slot.

The attach-time validator sph_validate_header checks the header scalars and region layout against the file size, but does not validate the array contents it then trusts. sph_walk_cell reads entries[buckets[b]] and follows each entry's next link raw, and sph_alloc_slot writes through a file-stored free_head index, none bounded against the entry count (max_entries).

A local peer that can write the backing file can leave the header valid while poisoning the bucket chain and free list, so a query reads through an out-of-bounds bucket and next index and an insert writes through an out-of-bounds free-list head, corrupting memory or crashing the process.

Weakness: CWE-787 (Out-of-bounds Write), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-59146?


## How do I fix CVE-2026-59146?

No fix has been published for CVE-2026-59146 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-59146 being exploited?

There is no known exploitation of CVE-2026-59146 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-59146 and fix it if it is affected.

What it is: CVE-2026-59146 is a high-severity memory corruption vulnerability in EGOR Data::SpatialHash::Shared, published on 21 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-59146 in the wild and no public exploit code.

Affected product: EGOR Data::SpatialHash::Shared. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-59146/ (Markdown: https://insights.sbomify.com/CVE-2026-59146/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-59146
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-59146
- OSV: https://osv.dev/vulnerability/CVE-2026-59146

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-59146/
Summaries are generated and may contain mistakes; the official description above is the record.