What is CVE-2019-12255?

CVE-2019-12255 is a critical-severity vulnerability in Belden Garrettcom Magnum Dx940e, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2019-08-09.

How severe is CVE-2019-12255?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2019-12255 known to be exploited?

5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Belden Garrettcom Magnum Dx940e

CVE-2019-12255

Wind River VxWorks has a Buffer Overflow in the TCP component (issue 1 of 4). This is a IPNET security vulnerability: TCP Urgent Pointer = 0 that leads to an integer underflow.

Vulnerability class: Buffer Overflow

Published 2019-08-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.751 (99.5th percentile), scored 2026-10-17.

High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.752 · newest: 0.751 · change: -0.002

Affected products

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

Public proof-of-concept exploits

References

support2.windriver.com/index.php (Issue Tracking, Vendor Advisory)
psirt.global.sonicwall.com/vuln-detail/SNWLID-2019-0009 (Third Party Advisory)
cert-portal.siemens.com/productcert/pdf/ssa-632562.pdf (Third Party Advisory)
security.netapp.com/advisory/ntap-20190802-0001/ (Third Party Advisory)
www.windriver.com/security/announcements/tcp-ip-network-stack-ipnet-urgent11/ (Vendor Advisory)
support2.windriver.com/index.php (Vendor Advisory)
packetstormsecurity.com/files/154022/VxWorks-6.8-Integer-Underflow.html (Exploit, VDB Entry, Third Party Advisory)
support.f5.com/csp/article/K41190253 (Third Party Advisory)
cert-portal.siemens.com/productcert/pdf/ssa-189842.pdf (Third Party Advisory)
support.f5.com/csp/article/K41190253

Frequently asked questions

What is CVE-2019-12255?: CVE-2019-12255 is a critical-severity vulnerability in Belden Garrettcom Magnum Dx940e, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2019-08-09.
How severe is CVE-2019-12255?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2019-12255 known to be exploited?: 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.