What is CVE-2021-39497?

CVE-2021-39497 is a critical-severity vulnerability in Eyoucms, classified under Server-Side Request Forgery (SSRF). CVSS score: 9.8/10. Published 2021-09-07.

How severe is CVE-2021-39497?

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

Is CVE-2021-39497 known to be exploited?

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

SSRF in Eyoucms

CVE-2021-39497

eyoucms 1.5.4 lacks sanitization of input data, allowing an attacker to inject a url to trigger blind SSRF via the saveRemote() function.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published 2021-09-07 · 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: 0.024 (83.2th percentile), scored 2026-10-06.

Low probability of exploitation in the next 30 days, but still tracked. 83rd percentile — 83.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.024 · newest: 0.024 · change: 0.000

Affected products

Eyoucms — versions 1.5.4

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

Public proof-of-concept exploits

References

github.com/eyoucms/eyoucms/releases/tag/v1.5.4 (Third Party Advisory)
hptcybersec.com/ssrf_PoC.jpg (Broken Link)
github.com/KietNA-HPT/CVE (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-39497?: CVE-2021-39497 is a critical-severity vulnerability in Eyoucms, classified under Server-Side Request Forgery (SSRF). CVSS score: 9.8/10. Published 2021-09-07.
How severe is CVE-2021-39497?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-39497 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.