9.8

CVE-2026-66583: wordpress forminator Deserialization of Untrusted Data

CVSS: 9.8v3.1CriticalDeferred
Published 20-08-2026Last modified 20-08-2026
Open JSON

Vulnerability summary

CVE-2026-66583 is a critical (CVSS 9.8) Deserialization of Untrusted Data vulnerability in wordpress forminator. EPSS estimates a 0.56% chance of exploitation in the next 30 days, higher than 45.7% of scored vulnerabilities. Fixed in 1.57.1.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.56%
0%100%
Low · +0.18 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 20-08-2026
    PublishedVulnerability first disclosed.
  2. 20-08-2026
    Last modifiedVulnerability information updated.

Description

Unauthenticated PHP Object Injection in Forminator <= 1.57.0 versions.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.56%

Chance of exploitation in the next 30 days

Percentile

46%

Versus all other CVEs

30-day change

+0.18 pp

From 0.39% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.56%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Wordpress1 product
  • forminator≤ 1.57.0 (fixed in 1.57.1)
Wpmu dev1 product

2 vendors · 2 products

References

2 links