What is CVE-2026-33657?

CVE-2026-33657 is a medium-severity vulnerability in Espocrm, classified under Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). CVSS score: 4.6/10. Published 2026-04-13.

How severe is CVE-2026-33657?

Medium severity. CVSS v3 base score is 4.6 out of 10.

Is CVE-2026-33657 known to be exploited?

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

XSS in Espocrm

CVE-2026-33657

EspoCRM is an open source customer relationship management application. Versions 9.3.3 and below have a stored HTML injection vulnerability that allows any authenticated user with standard (non-administrative) privileges to inject arbitrar…

EPSS: 0.000 (10.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.6 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N.

Affected products

Espocrm — versions < 9.3.4

Weakness classification (CWE)

Public proof-of-concept exploits

EntroVyx/CVE-2026-33657

References

https://github.com/espocrm/espocrm/security/advisories/GHSA-8prm-r5j9-j574 (x_refsource_CONFIRM)
https://github.com/espocrm/espocrm/releases/tag/9.3.4 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-33657?: CVE-2026-33657 is a medium-severity vulnerability in Espocrm, classified under Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). CVSS score: 4.6/10. Published 2026-04-13.
How severe is CVE-2026-33657?: Medium severity. CVSS v3 base score is 4.6 out of 10.
Is CVE-2026-33657 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.