What is CVE-2022-37839?

CVE-2022-37839 is a critical-severity vulnerability in Totolink A860r, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2022-09-06.

How severe is CVE-2022-37839?

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

Is CVE-2022-37839 known to be exploited?

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

Buffer overflow in Totolink A860r

CVE-2022-37839

TOTOLINK A860R V4.1.2cu.5182_B20201027 is vulnerable to Buffer Overflow via Cstecgi.cgi.

Vulnerability class: Buffer Overflow

Published 2022-09-06 · 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: 0.009 (59.2th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 59.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.001

Affected products

Totolink A860r
Totolink A860r Firmware — versions 4.1.2cu.5182_b20201027

Weakness classification (CWE)

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

Public proof-of-concept exploits

References

github.com/1759134370/iot/blob/main/TOTOLINK/A860R/5.md (Third Party Advisory, Broken Link)

Frequently asked questions

What is CVE-2022-37839?: CVE-2022-37839 is a critical-severity vulnerability in Totolink A860r, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2022-09-06.
How severe is CVE-2022-37839?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2022-37839 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.