CVE-2026-83627
CriticalCVSS 9.8Exploitation Probability (EPSS)
Elevated risk55th percentile - higher than 55% of all known CVEs
Summary
The Hummingbird plugin for WordPress (versions up to and including 3.21.0) is vulnerable to Remote Code Execution via the log_msg() function in class-page-cache.php. The protective '<?php die(); ?>' header is omitted due to a class_exists() namespace bug, and cookie names with the wphb_cache_ prefix are written to the log file without sanitization, allowing an unauthenticated attacker to write and execute arbitrary PHP.
Risk Assessment
An unauthenticated attacker can remotely execute arbitrary PHP code on the server, leading to full compromise of the WordPress site. This requires the non-default Page Caching with Debug Log option to be enabled.
Recommendation
Update the Hummingbird plugin to a version newer than 3.21.0, or if not possible, disable the Page Caching with Debug Log option and remove log files from the wp-content/wphb-logs/ directory.
Related vulnerabilities
- CVE-2026-122992Critical
In G4KLX DStarGateway and F4FXL DStarGateway before 7b75de6, dstarCallsignToAPRS in APRSUtils.cpp has an integer underflow via an empty RS-MS1A sender field.
- CVE-2026-122321Critical
Kyverno 1.18.0 before 1.19.2 contains a signature verification bypass in verifyImages because cached verification results are keyed by the image reference string (such as a tag) rather than bound to the verified digest, so cache hits skip signature and attestation checks. An attacker who can submit workloads and move a registry tag can warm the cache with a signed image, repoint the tag, and have Kyverno admit the workload and use mutateDigest to pin the unverified digest.
- CVE-2026-122313Critical
Kyverno from 1.17.0 before 1.19.2 contains a privilege escalation vulnerability that allows namespace-scoped tenants to modify resources in other namespaces through NamespacedMutatingPolicy targetMatchConstraints.expression CEL output lacking namespace checks. Attackers can emit a literal target such as another tenant's RoleBinding, which the cluster-wide background controller then mutates to add attacker subjects or alter Roles, NetworkPolicies, and ConfigMaps.
- CVE-2026-122311Critical
Kyverno from 1.16.0 before 1.19.2 fails to validate path segments in the resource argument of resource.get() and resource.post(), allowing namespaced CEL policies to escape their namespace. Tenants who can create a NamespacedValidatingPolicy can insert .. segments to read and write arbitrary cluster objects using the admission controller's ServiceAccount, leading to cluster takeover.
- CVE-2026-122310Critical
Kyverno from 1.19.1 before 1.19.2 validates a Policy's context.apiCall urlPath after cleaning it but executes the raw path, whose fragment or query the Kubernetes client discards. A namespace-scoped user who can create a Policy can hide ../ segments behind # or ? to reach cluster-scoped endpoints with Kyverno's ServiceAccount, gaining cluster admin.
- CVE-2026-122304Critical
Kyverno from 1.17.0 before 1.19.2 contains an authorization bypass vulnerability that allows namespace admins to escape namespace confinement because the cleanup controller builds its context loader with a nil policy. Attackers can create a namespaced CleanupPolicy with apiCall or globalReference context entries to read cross-namespace Secrets and modify validatingwebhookconfigurations using the cleanup controller's ServiceAccount.
- CVE-2026-122303Critical
Kyverno from 1.17.0 before 1.19.2 contains an authorization bypass vulnerability that allows namespace tenants to overwrite resources in other namespaces via NamespacedMutatingPolicy mutate-existing targetMatchConstraints.expression. Attackers can return a CEL map literal fabricating a target with an attacker-chosen metadata.namespace, causing the privileged background controller to overwrite Secrets, Deployments, or policies cluster-wide.
- CVE-2026-122302Critical
Kyverno before 1.19.2 contains a privilege escalation vulnerability that allows namespace admins to create resources beyond their RBAC because generate-rule admission checks verify the controller's permissions, not the author's. Attackers can create a namespaced Policy with generate rules targeting other namespaces or cluster-scoped kinds, making the background controller create or clone resources cluster-wide.
- CVE-2026-122051Critical
A flaw was found in Edimax BR-6208AC version 1.32 in an unknown functionality of the /goform/mp file. Input manipulation can lead to command injection. The attack can be launched remotely and the exploit has been published.
- CVE-2026-54384Critical
VitaFit cloud API before 2026-10-30 contained an authentication bypass vulnerability that allows remote attackers to obtain a full session for a victim's account by submitting a linked Google or Facebook account identifier to the POST /front/login/sns/ endpoint without providing proof of ownership from the identity provider. Attackers can forge a login using an identifier exposed through account enumeration to read and modify the victim's profile and delete the account's authentication record.
Original NVD description (English source)
The Hummingbird – Speed Optimization, Caching, Minify, Compress & CDN plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 3.21.0 via the log_msg() function in core/modules/class-page-cache.php. The page-cache debug log is written to wp-content/wphb-logs/page-caching-log.php, a directly web-accessible PHP file that is supposed to be protected by a leading '<?php die(); ?>' header. That header is guarded by class_exists( 'Filesystem' ), which can never match because class_exists() resolves string arguments in the global namespace while the class is Hummingbird\Core\Filesystem; when the log is created during a front-end request the header is therefore omitted entirely. get_cookies() then writes the raw name of any cookie matching the wphb_cache_ prefix into that file without sanitization. This makes it possible for unauthenticated attackers to write arbitrary PHP into the log file with a single anonymous request and execute it by requesting the file directly, resulting in full remote code execution. Exploitation requires the site administrator to have enabled Page Caching with the Debug Log option (non-default), and the log file to be created during a front-end request — a state reached by the plugin's own 'Clear logs' action, any cache flush, or unattended via the plugin's daily log-rotation cron, which can strip the protective header from an existing log file.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

