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NVD / CVE Program· CNA Wordfence

CVE-2021-42362: WordPress Popular Posts <= 5.3.2 Authenticated Arbitrary File Upload

Noroxi assessment

Priority: Plan (action score 59/100)

  • A ready-made attack module is public (Metasploit); exploiting it takes no special expertise.
  • Public proof-of-concept code exists (Exploit-DB, GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 79.8% (FIRST EPSS); higher than 99.6% of all records.
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • No fixed version is recorded, but the references include a patch (commit or PR) link.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Add it to your regular patch cycle. See the fix and affected versions sections below.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

The WordPress Popular Posts WordPress plugin is vulnerable to arbitrary file uploads due to insufficient input file type validation found in the ~/src/Image.php file which makes it possible for attackers with contributor level access and above to upload malicious files that can be used to obtain remote code execution, in versions up to and including 5.3.2.

HighCVSS 8.8 · v3.1—Weaponized No fix recorded
Published
Nov 17, 2021
Updated
Jun 17, 2026
EPSS
79.8% · 99th percentile

Report tools

JSON

Action score

59

Plan

Add it to your regular patch cycle.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
24 / 30 · 79.8%

CNA vs NVD score

NVD
—
CNA · Wordfence
8.8
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
wordpress popular posts projectwordpress popular posts

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • wordpress popular posts project wordpress popular postsup to 5.3.2 inclusive

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Wordfence). Independent of NVD's CPE analysis and usually ahead of it.

  • WordPress Popular Posts WordPress Popular Posts

    • 0.0 and later · up to and including 5.3.2affected

Same product

wordpress popular posts project: all records

Other highest-scoring records for the same primary product.

  • CVE-2022-43468External initialization of trusted variables or data stores vulnerability exists in WordPress Popular Posts 6.0.5 and earlier, therefore the
    30Monitor
  • CVE-2023-45607WordPress WordPress Popular Posts Plugin <= 6.3.2 is vulnerable to Cross Site Scripting (XSS)
    21Monitor
  • CVE-2021-36872WordPress Popular Posts plugin <= 5.3.3 - Authenticated Persistent Cross-Site Scripting (XSS) vulnerability
    21Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2021-20746Jun 27, 2021 · Cross-site scripting vulnerability in WordPress Popular Posts 5.3.2 and earlier allows a remote authenticated attacker to inject an arbitrar
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

  • Metasploit module ×1
  • Exploit-DB entry ×1
  • Proof-of-concept repository on GitHub ×2

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Exploit-DB entrywebapps2021-07-15
Metasploit moduleexploit/multi/http/wp_popular_posts_rceWordpress Popular Posts Authenticated RCEexploit2021-06-11
Proof-of-concept repository on GitHubstars:02021-07-14
Proof-of-concept repository on GitHubstars:02025-04-14

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Metasploit-160 d
  2. First PoC-127 d
  3. Published
  4. TodayNov 10, 2026+1819 d

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-434 · Unrestricted Upload of File with Dangerous Type

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records