CVE-2026-39556: WordPress Konsept theme <= 1.9 - PHP Object Injection vulnerability
Unauthenticated PHP Object Injection in Konsept <= 1.9 versions.
Metrics
- CVSS v3.1
- 8.1
- Severity
- HIGH
- Fixed in
- —
- Affected Products
- 1
HarborGuard Analysis
Synopsis
PHP Object Injection is an unauthenticated vulnerability in the Elated-Themes Konsept WordPress theme, affecting versions 1.9 and earlier. The flaw is reachable over the network without any credentials, though certain environmental conditions must align for exploitation to succeed. A successful attacker can read sensitive data, tamper with site content, and crash the affected service. HarborGuard tracks this advisory and will make a patched-image rebuild available the moment an upstream fix is published.
HarborGuard Coverage
Detection capability is available across every HarborGuard environment: the CVE is ingested from upstream feeds (including Patchstack) within minutes of publication and matched against customer images in connected registries and CI/CD pipelines, covering custom-built images that bundle the Konsept theme. Matching runs continuously, so images added or rebuilt after the CVE was published are evaluated automatically.
AvailableHarborGuard scores this finding at CVSS 8.1 (HIGH) and is capable of weighting that score against each customer environment's compliance policy to surface the finding at the correct severity tier. Routing to the appropriate team inbox within each customer organization is handled automatically based on configured ownership rules.
AvailableNo upstream fix version has been published for this CVE. HarborGuard re-checks the Patchstack advisory on every ingest cycle and will make a patched-image rebuild available the moment a fix version is released upstream. For customers who opt into auto-remediation, the rebuild, regression-test run, and PR against affected workloads will trigger automatically at that point.
Pending upstreamExploit Conditions
- Network reachabilityRequired
The vulnerable theme endpoint is exposed over the network, so an attacker must be able to reach the WordPress installation via HTTP/HTTPS to deliver a malicious serialized payload.
- AuthenticationNot required
No account or session token is needed; the injection point accepts unauthenticated requests.
- Victim interactionNot required
The attack is entirely server-side and requires no action from a site visitor or administrator.
- Attack complexityDetail
Exploitation is rated High complexity, meaning the attacker must account for environmental factors such as the presence of a suitable PHP gadget chain in the installed dependency set before the payload can execute.
Blast Radius
- A successful attacker can read sensitive server-side data, including WordPress configuration values, database credentials, and stored user records.
- The attacker can modify persisted data: altering database rows, injecting content, or replacing theme files accessible to the PHP process.
- The attacker can crash or destabilize the WordPress service by triggering destructors that exhaust memory or corrupt runtime state.
How HarborGuard Handles This
Available on HarborGuard: detection for CVE-2026-39556 is active for all connected registries and pipelines, matching any image that bundles the Konsept theme at version 1.9 or earlier. Because no upstream patch exists yet, HarborGuard monitors the Patchstack advisory on every ingest cycle and will trigger the rebuild-and-PR flow automatically for customers with auto-remediation enabled the moment a fix version is published. In the interim, compensating controls worth considering include placing the WordPress installation behind a web application firewall rule that blocks deserialization-pattern payloads, restricting network-policy egress from the container to limit post-exploitation reach, and auditing installed plugins and themes for gadget-chain candidates that would make the injection exploitable in your specific environment.
- Elated-Themes / Konsept≤ 1.9
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H