What is CVE-2019-11837?

CVE-2019-11837 is a high-severity vulnerability in F5 Njs, classified under CWE-189. CVSS score: 7.5/10. Published 2019-05-09.

How severe is CVE-2019-11837?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in F5 Njs

CVE-2019-11837

njs through 0.3.1, used in NGINX, has a segmentation fault in String.prototype.toBytes for negative arguments, related to nxt_utf8_next in nxt/nxt_utf8.h and njs_string_offset in njs/njs_string.c.

Published 2019-05-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.014 (71.0th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

F5 Njs

Weakness classification (CWE)

CWE-189

References

github.com/nginx/njs/issues/155 (Exploit, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2019-11837?: CVE-2019-11837 is a high-severity vulnerability in F5 Njs, classified under CWE-189. CVSS score: 7.5/10. Published 2019-05-09.
How severe is CVE-2019-11837?: High severity. CVSS v3 base score is 7.5 out of 10.