What is CVE-2021-39999?

CVE-2021-39999 is a high-severity vulnerability in Huawei Ese620x Vess, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.5/10. Published 2022-07-12.

How severe is CVE-2021-39999?

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

Buffer overflow in Huawei Ese620x Vess

CVE-2021-39999

There is a buffer overflow vulnerability in eSE620X vESS V100R001C10SPC200 and V100R001C20SPC200. An attacker can exploit this vulnerability by sending a specific message to the target device due to insufficient validation of packets. Successful exploit could cause a denial of service condition.

Vulnerability class: Buffer Overflow

Published 2022-07-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.007 (50.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: +0.000

Affected products

Huawei Ese620x Vess
Huawei Ese620x Vess Firmware — versions v100r001c10spc200, v100r001c20spc200
Ese620x Vess — versions V100R001C10SPC200,V100R001C20SPC200

Weakness classification (CWE)

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

References

www.huawei.com/en/psirt/security-advisories/huawei-sa-20211201-01-buffer-en (Vendor Advisory)

Frequently asked questions

What is CVE-2021-39999?: CVE-2021-39999 is a high-severity vulnerability in Huawei Ese620x Vess, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.5/10. Published 2022-07-12.
How severe is CVE-2021-39999?: High severity. CVSS v3 base score is 7.5 out of 10.