Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Privileges required (PR:L) | Low privileges required |
| User interaction (UI:N) | No user interaction |
| Scope (S:U) | Scope unchanged |
| Confidentiality (C:H) | High confidentiality impact |
| Integrity (I:H) | High integrity impact |
| Availability (A:H) | High availability impact |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
About Kirki
CVE-2026-75891 affects Kirki. Before acting, confirm where Kirki runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: The Kirki plugin for WordPress is vulnerable to Privilege Escalation via PHP Object Injection in all versions up to, and including, 6.2.5 via deserialization of untrusted input through the 'get-single-symbol' branch of the kirki_post_apis() AJAX dispatcher due to a missing capability check. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject a PHP Object. The additional presence of a POP chain allows attackers to overwrite an administrator's password and gain administrative access.
The weakness class is Deserialization of Untrusted Data. The application rebuilds objects from attacker controlled data, which can run code.
Based on its CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Kirki |
| Affected versions | See the vendor advisory under Technical References |
| Published | Oct 27, 2026 |
| Last modified | Oct 27, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security@wordfence.com |
How to detect it
- Inventory every instance of Kirki and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Kirki named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Kirki to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-502: Deserialization of Untrusted Data More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
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