What is CVE-2019-19720?

CVE-2019-19720 is a high-severity vulnerability in Yabasic, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2019-12-11.

How severe is CVE-2019-19720?

High severity. CVSS v3 base score is 8.8 out of 10.

Buffer overflow in Yabasic

CVE-2019-19720

Yabasic 2.86.1 has a heap-based buffer overflow in the yylex() function in flex.c via a crafted BASIC source file.

Vulnerability class: Buffer Overflow

Published 2019-12-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.014 (73.2th percentile), scored 2026-10-26.

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 73.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.014 · change: +0.002

Affected products

Yabasic — versions 2.86.1

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

github.com/marcIhm/yabasic/issues/36 (Exploit, Third Party Advisory)
www.yabasic.de/whatsnew.html (Release Notes, Vendor Advisory)

Frequently asked questions

What is CVE-2019-19720?: CVE-2019-19720 is a high-severity vulnerability in Yabasic, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2019-12-11.
How severe is CVE-2019-19720?: High severity. CVSS v3 base score is 8.8 out of 10.