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CVE.org (no NVD analysis yet)· CNA Wordfence

CVE-2026-2839: Advanced Custom Fields: Extended <= 0.9.2.7 - Missing Authorization to Unauthenticated Data Exposure via Multiple AJAX Endpoints

Noroxi assessment

Priority: Monitor (action score 21/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.27% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: hwk-fr Advanced Custom Fields: Extended 0.9.2.4.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to hwk-fr Advanced Custom Fields: Extended 0.9.2.4 or later.

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 Advanced Custom Fields: Extended plugin for WordPress is vulnerable to unauthorized access of data and triggering of server-side actions in all versions up to, and including, 0.9.2.7. This is due to multiple AJAX handlers registered for unauthenticated users (`wp_ajax_nopriv_*`) that fail to implement proper `current_user_can()` authorization checks. While these handlers use ACF's `acf_verify_ajax()` function to validate cryptographic nonces, the `acf_nonce` values are generated for guest users and publicly exposed in the page source of any frontend page utilizing an ACF form. This makes it possible for unauthenticated attackers to extract the guest nonce and bypass WordPress visibility permissions, leading to the unauthorized disclosure of post titles and internal Flexible Content layout structures. The vulnerability was partially patched in version 0.9.2.4.

MediumCVSS 5.3 · v3.1—No exploit Fix available
Published
Oct 28, 2026
Updated
Oct 29, 2026
EPSS
0.2% · 19th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Wordfence
5.3
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 exploit code appears or is weaponized
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  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

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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.

—

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.

  • hwk-fr Advanced Custom Fields: Extended

    • up to and including 0.9.2.7affected · semver

Same product

hwk-fr: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-13486Advanced Custom Fields: Extended 0.9.0.5 - 0.9.1.1 - Unauthenticated Remote Code Execution in prepare_form
    60This week
  • CVE-2026-8809Advanced Custom Fields: Extended <= 0.9.2.5 - Unauthenticated Privilege Escalation via Validation Bypass to '_acf_post_id' Parameter
    39Monitor
  • CVE-2025-14533Advanced Custom Fields: Extended <= 0.9.2.1 - Unauthenticated Privilege Escalation via Insert User Form Action
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2025-15463May 12, 2026 · Advanced Custom Fields: Extended <= 0.9.2.3 - Unauthenticated Arbitrary Shortcode Execution
    26Monitor
  • ← EarlierCVE-2026-10752Oct 27, 2026 · Advanced Custom Fields: Extended <= 0.9.2.6 - Missing Authorization to Unauthenticated Arbitrary Attachment Deletion via Email Action Dynamic File Field
    19Monitor
  • Later →CVE-2026-110305Oct 30, 2026 · Advanced Custom Fields: Extended <= 0.9.2.7 - Unauthenticated Sensitive Information Exposure in 'acf[<mapped_field>]' Parameter via {get_user} Template Tag Inje
    30Monitor

Remediation

Which version to upgrade to

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

Product / packageFixed versionSource
hwk-fr Advanced Custom Fields: Extended0.9.2.4 · descriptionVendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

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. Published
  2. Fix recordedsame day
  3. TodayOct 31, 2026+3 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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.

  • CVE-2026-107521 days apartAdvanced Custom Fields: Extended <= 0.9.2.6 - Missing Authorization to Unauthenticated Arbitrary Attachment Deletion via Email Action Dynamic File Field
    19Monitor

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.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
low · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-862 · Missing Authorization

CVSS vector

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

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

  1. SSVC exploitation— → none
  2. Exploit maturity— → none
  3. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (6 more)

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

All records