Security readout for executives and security teams
Plain-English summary
A public-facing WordPress site using Mailgun for WordPress through version 2.2.0 may let an unauthenticated attacker misuse the site’s Mailgun credentials. The reported impact includes creating email-forwarding routes, intercepting password-reset messages, and potentially taking over administrator accounts.
Executive priority
Treat affected, internet-accessible installations as an immediate remediation priority because reported abuse could expose email and enable administrator takeover. Establish exposure today, follow vendor guidance, and investigate Mailgun routes and account activity. Avoid declaring compromise solely from version detection.
Technical view
Insufficient validation in add_list() reportedly allows attacker-controlled keys in the addresses POST array to alter the Mailgun API path. The plugin sanitizes these keys as text but does not adequately prevent path traversal, enabling unauthenticated requests that the site authenticates with its Mailgun API key.
Likely exposure
Exposure is likely where Mailgun for WordPress version 2.2.0 or earlier is active and configured with a usable Mailgun API key. The supplied evidence does not establish whether every configuration is reachable or exploitable. The affected-version metadata contains an inconsistent “0” entry, while the description explicitly states versions through 2.2.0.
Exploitation context
The supplied bundle reports a low-complexity, unauthenticated attack path with severe confidentiality, integrity, and availability consequences. However, the CVE is not marked as KEV, and no supplied source establishes active exploitation, public exploit availability, or observed attacks.
Researcher notes
The core issue is path manipulation through attacker-controlled addresses array keys before authenticated Mailgun API requests. Supplied code references support review of add_list() and related request construction. Evidence is incomplete regarding a fixed version, vendor-endorsed workaround, configuration prerequisites, active exploitation, and the inconsistent structured affected-version entry.
Mitigation direction
- Inventory WordPress sites running Mailgun for WordPress and record installed versions.
- Check current Mailgun or plugin vendor guidance for a confirmed fixed release or mitigation.
- Consider disabling the plugin until confirmed safe, accounting for email-delivery dependencies.
- Rotate the Mailgun API key if misuse is suspected, then update dependent configuration.
- Review and remove unauthorized Mailgun routes using approved administrative processes.
Validation and detection
- Confirm whether Mailgun for WordPress version 2.2.0 or earlier is installed and active.
- Determine whether the plugin stores a valid Mailgun API key.
- Inspect Mailgun audit activity for unexpected API requests or configuration changes.
- Review inbound routes for unauthorized forwarding destinations or recent additions.
- Investigate unusual password-reset emails, administrator changes, and account-access events.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-918: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCloud metadata behavior lookup
The CVE wording references SSRF or metadata access, so cloud discovery and credential material review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-78003 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9WordfenceVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineWordfence
Disclosed
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/110e888d-69fc-4682-b908-2b62288c5227?source=cveCVE reference, Wordfence
- https://plugins.trac.wordpress.org/browser/mailgun/trunk/mailgun.php#L557CVE reference, Wordfence
- https://plugins.trac.wordpress.org/browser/mailgun/tags/2.1.10/mailgun.php#L259CVE reference, Wordfence
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Server-Side Request Forgery
Server-Side Request Forgery represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.