8.1

CVE-2023-4386: wordpress essential-blocks Deserialization of Untrusted Data

CVSS: 8.1v3.1HighModified
Published 20-10-2023Last modified 08-04-2026
Open JSON

Vulnerability summary

CVE-2023-4386 is a high (CVSS 8.1) Deserialization of Untrusted Data vulnerability in wordpress essential-blocks. EPSS estimates a 0.88% chance of exploitation in the next 30 days, higher than 58.4% of scored vulnerabilities. Fixed in 4.2.1 and 1.1.1.

Overall risk
33/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.88%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 20-10-2023
    PublishedVulnerability first disclosed.
  2. 08-04-2026
    Last modifiedVulnerability information updated.

Description

The Essential Blocks plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 4.2.0 via deserialization of untrusted input in the get_posts function. This allows unauthenticated attackers to inject a PHP Object. No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.88%

Chance of exploitation in the next 30 days

Percentile

58%

Versus all other CVEs

30-day change

+0.02 pp

From 0.86% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.88%

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

Wordpress2 products
  • essential-blocks≤ 4.2.0 (fixed in 4.2.1)
  • essential-blocks-pro≤ 1.1.0 (fixed in 1.1.1)
Wpdevteam2 products
Wpdeveloper1 product

3 vendors · 5 products

References

3 links