Critical 10.0Published May 1, 2026

CVE-2026-42996JS8Call 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.

Updated under an hour ago (Oct 27, 2026, 4:00 AM ET)

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Exploited in the last 30 days

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.

CVSS: 10.0 CRITICAL (v4.0, CNA)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
Weakness (CWE): CWE-121
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Deferred
Record last updated: May 1, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

JS8Call JS8Call js8call:js8call (from the name)	through 2.3.1	CNA record
JS8Call-improved JS8Call-improved js8call_improved:js8call_improved (from the name)	before 3.0	CNA record

References

References

https://github.com/JS8Call-improved/JS8Call-improved/security/advisories/GHSA-98hp-pjp7-w62x
https://amateur-radio-resources.sourceforge.io/PDF/JS8APRS.pdf
https://github.com/js8call/js8call/blob/fd721e8b67eed84cb3c09d018205ab9a53e1a8b1/APRSISClient.cpp#L89-L102
https://github.com/JS8Call-improved/JS8Call-improved/commit/a6c7a19b82bbd7c2c0c892576f84d7449e8c7088

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.