CVE-2026-86863
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk30th percentile - higher than 30% of all known CVEs
Summary
In pgAdmin 4, the 'webserver' authentication source was vulnerable because WebserverAuthentication.get_user() fell back to reading the username directly from inbound HTTP request headers when the WSGI/CGI environment lookup returned nothing. As a result, any client able to reach pgAdmin could supply that header itself and authenticate as any username, including an existing Administrator, without a password. The issue affects versions from 6.2 before 9.18 and only applies when 'webserver' is enabled in AUTHENTICATION_SOURCES.
Risk Assessment
An attacker with network access to pgAdmin can gain full administrative privileges without any credentials, leading to compromise of managed database servers and data. The risk is especially high when pgAdmin is exposed to a network or when the 'webserver' source is active in the configuration.
Recommendation
Upgrade pgAdmin 4 to version 9.18 or later, and if web server authentication is not used, remove 'webserver' from AUTHENTICATION_SOURCES. After upgrading, if you rely on this mechanism, enable it explicitly via WEBSERVER_REMOTE_USER_FROM_HEADER, configure WEBSERVER_TRUSTED_PROXIES and WEBSERVER_SHARED_SECRET, and avoid exposing pgAdmin directly to the network.
Other vulnerabilities in pgAdmin 4
See all- CVE-2026-116241Critical
pgAdmin 4 before 9.19 contains a bypass of the CVE-2026-17566 fix in the Import/Export Data tool. Improper validation of a backslash inside a double-quoted identifier hides a closing parenthesis and executes a TO PROGRAM clause via psql on the pgAdmin host with the OS account privileges.
- CVE-2026-17566Critical
A vulnerability in pgAdmin 4 allows remote code execution (RCE) via injection into the Import/Export Data tool. The validation function incorrectly handles backslashes in SQL strings, enabling bypass of protections and addition of a TO PROGRAM clause to psql commands.
- CVE-2026-17351Critical
A vulnerability in pgAdmin 4 (versions 9.13 to 9.16) allows bypassing the CVE-2026-12045 fix by injecting SQL queries into the AI assistant. An attacker can plant a malicious payload in an object read by the assistant, leading to execution of multiple SQL statements, including write or remote code execution.
- CVE-2026-17349Critical
In the adhoc_connect_server function in pgAdmin 4 9.0-9.16, when a non-owner user clones a server, all columns including credentials (passwords) and ownership flags are copied. This allows an attacker to take over the cloned server and use database passwords belonging to another user (e.g., an administrator).
- CVE-2026-12048Critical
A stored cross-site scripting vulnerability exists in pgAdmin 4 versions 6.0 through 9.15. Text returned by a PostgreSQL server (e.g., object names in errors or EXPLAIN fields) was passed verbatim to html-react-parser, allowing injection of arbitrary HTML, including iframes. An attacker controlling the server or creating a maliciously named object can hijack the victim's pgAdmin session.
- CVE-2026-12046Critical
In pgAdmin 4 versions 6.9 through 9.15, two SQL Editor endpoints lack authentication decorators, allowing unauthenticated attackers to trigger pickle deserialization from server sessions. Exploitation requires additional preconditions (knowledge of SECRET_KEY and write access to sessions directory) to achieve remote code execution.
- CVE-2026-12045Critical
A vulnerability in the pgAdmin 4 AI Assistant allows an attacker who can influence database content read by the assistant to execute arbitrary SQL with the privileges of the pgAdmin user's database role. The flaw stems from missing validation of LLM-generated queries, enabling bypass of read-only mode via injection of commands like COMMIT or ROLLBACK.
- CVE-2026-7813Critical
In pgAdmin 4 server mode, multiple endpoints fetched user-owned objects without filtering by the requesting user's identity, allowing an authenticated user to access another user's private servers, server groups, background processes, and debugger arguments by guessing object IDs. The Shared Servers feature had additional issues including credential leakage, privilege escalation via writable passexec_cmd enabling arbitrary command execution, and owner-data corruption.
- CVE-2025-13780Critical
pgAdmin versions up to 9.10 are affected by a Remote Code Execution (RCE) vulnerability that occurs when running in server mode and performing restores from PLAIN-format dump files. This issue allows attackers to inject and execute arbitrary commands on the server hosting pgAdmin.
- CVE-2025-12762Critical
pgAdmin versions up to 9.9 are affected by a Remote Code Execution (RCE) vulnerability when running in server mode and performing restores from PLAIN-format dump files. Attackers can inject and execute arbitrary commands on the server hosting pgAdmin.
Original NVD description (English source)
pgAdmin 4's Webserver authentication source is intended to accept an identity asserted by the web server or reverse proxy in front of pgAdmin, delivered through the WSGI/CGI environment. WebserverAuthentication.get_user() read config.WEBSERVER_REMOTE_USER from request.environ and, when that returned nothing, fell back to reading the same name directly from the inbound HTTP request headers via request.headers.get(). An inbound HTTP header is written by whoever sends the request, so any client able to reach pgAdmin could supply that header itself and be authenticated as any username it named, including an existing Administrator, without presenting a password or any other credential. The environment lookup could also be satisfied by a client-supplied header whenever WEBSERVER_REMOTE_USER was configured to an HTTP_-prefixed or hyphenated name such as HTTP_X_FORWARDED_USER or X-Forwarded-User, since WSGI servers place inbound headers into the environment under exactly those names. Deployments are affected only when 'webserver' is enabled in AUTHENTICATION_SOURCES. The fix distinguishes a genuine CGI/WSGI variable from a header-derived one and implicitly trusts only the former. A header-asserted identity is now accepted only when the operator explicitly opts in via WEBSERVER_REMOTE_USER_FROM_HEADER, the request arrives from a peer listed in WEBSERVER_TRUSTED_PROXIES, and, when configured, a shared secret supplied in WEBSERVER_SHARED_SECRET_HEADER matches WEBSERVER_SHARED_SECRET under a constant-time comparison. The trusted-peer check deliberately reads the real socket peer address rather than request.remote_addr, because ProxyFix rewrites the latter from the client-controlled X-Forwarded-For header and would otherwise allow an attacker to claim to be the trusted proxy. As defence in depth, login() now refuses any account whose auth_source is not 'webserver', so a misconfigured trust gate cannot be used to assume an internal or LDAP account. This issue affects pgAdmin 4: from 6.2 before 9.18.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS