CVE-2021-24537 | Similar Posts <= 3.1.5 - Admin+ Arbitrary PHP Code Execution

Exp

The Similar Posts WordPress plugin through 3.1.5 allow high privilege users to execute arbitrary PHP code in an hardened environment (ie with DISALLOW_FILE_EDIT, DISALLOW_FILE_MODS and DISALLOW_UNFILTERED_HTML set to true) via the 'widget_rrm_similar_posts_condition' widget setting of the plugin.

Published: 2021-11-08 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-24537 is rated High Exploit Risk (69.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.51%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-24537

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-24537

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.98% 1.51% +0.53%
2 2025-03-30 22.17% 0.98% -21.19%
3 2025-03-29 22.17%

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-24537

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.2 5.9 [email protected]
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
6.8 6.4 [email protected]

Weakness enumeration for CVE-2021-24537

Affected software / configurations for CVE-2021-24537

Vendor Product Version Raw CPE
shareaholic similar_posts <= 3.1.5 cpe:2.3:a:shareaholic:similar_posts:*:*:*:*:*:wordpress:*:*

References for CVE-2021-24537

cvelogic Threat Intelligence