# CVE-2026-107612: World-accessible IPC shared memory with predictable name in TightVNC Server

> A local attacker can read or modify IPC shared memory in TightVNC Server due to weak permissions and predictable naming, potentially exposing session data or escalating privileges.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 8 Oct 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-95xq-4x4f-23hr

## What is CVE-2026-107612?

CVE-2026-107612 is a high-severity vulnerability in GlavSoft TightVNC, published on 8 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Incorrect permission assignment in GlavSoft TightVNC Server for Windows before 2.8.88 allows a local authenticated user to read or overwrite the inter-process communication handles used between the TightVNC service and its desktop server process. The named shared memory segment in the Global\ namespace that carries the pipe HANDLE values is created with a NULL DACL, and its name is derived from a time-seeded srand(time(0)) value that is predictable to one-second granularity. A low-privileged local process can open the mapping and tamper with the IPC channel of a service running as SYSTEM, potentially leading to disclosure of session data, privilege escalation, or denial of service.

Weakness: CWE-732 (Incorrect Permission Assignment for Critical Resource), CWE-338 (Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG))

## Which versions are affected by CVE-2026-107612?


## How do I fix CVE-2026-107612?

No fix has been published for CVE-2026-107612 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-107612 being exploited?

There is no known exploitation of CVE-2026-107612 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-107612 and fix it if it is affected.

What it is: CVE-2026-107612 is a high-severity vulnerability in GlavSoft TightVNC, published on 8 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-107612 in the wild and no public exploit code.

Affected product: GlavSoft TightVNC. 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-2026-107612/ (Markdown: https://insights.sbomify.com/CVE-2026-107612/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107612
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107612
- OSV: https://osv.dev/vulnerability/CVE-2026-107612

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-107612/
Summaries are generated and may contain mistakes; the official description above is the record.