# CVE-2026-42996: Memory corruption in JS8Call

> A stack-based buffer overflow in JS8Call allows remote attackers to execute arbitrary code or cause a denial of service via a malicious radio transmission.

- **Severity:** Critical 10.0 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/S:P/AU:Y/R:U/V:D/RE:M/U:Green`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 May 2026
- **Updated:** 1 May 2026
- **Also known as:** GHSA-98hp-pjp7-w62x, GHSA-j23g-7p7w-3f6j

## What is CVE-2026-42996?

CVE-2026-42996 is a critical memory corruption vulnerability in JS8Call, published on 1 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

JS8Call through 2.3.1 and JS8Call-improved before 3.0 have a stack-based buffer overflow via a radio transmission of @APRSIS GRID followed by a long Maidenhead locator. This occurs in grid2deg in APRSISClient.cpp.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2026-42996?


## How do I fix CVE-2026-42996?

No fix has been published for CVE-2026-42996 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-42996 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42996 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-42996 and fix it if it is affected.

What it is: CVE-2026-42996 is a critical memory corruption vulnerability in JS8Call, published on 1 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42996 exists.

Affected product: JS8Call. 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-2026-42996/ (Markdown: https://insights.sbomify.com/CVE-2026-42996/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-42996
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42996
- OSV: https://osv.dev/vulnerability/CVE-2026-42996

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-42996/
Summaries are generated and may contain mistakes; the official description above is the record.