CVE-2026-7818 pgAdmin 4: Unsafe deserialization (CWE-502) in file-backed session manager leads to remote code execution
An authenticated user with write access to the sessions directory can achieve remote code execution via unsafe deserialization in pgAdmin 4.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-7818?
CVE-2026-7818 is a high-severity unsafe deserialization vulnerability in pgadmin.org pgAdmin 4, published on 11 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Deserialization of untrusted data (CWE-502) in pgAdmin 4 FileBackedSessionManager.
The session manager performed unsafe deserialization of session-file contents (using Python's standard object-serialization module) before performing any HMAC integrity check. Any file dropped into the sessions directory was deserialized unconditionally. An authenticated user with write access to the sessions directory (whether by misconfiguration or in combination with another path-traversal flaw) could plant a crafted serialized payload to achieve operating-system level remote code execution under the pgAdmin process identity.
Fix prepends a 64-byte hex SHA-256 HMAC over the session body, computed with SECRET_KEY, and verifies it via hmac.compare_digest before any deserialization. The check is raised (rather than asserted) on empty SECRET_KEY so it is not stripped under -O.
This issue affects pgAdmin 4: before 9.15.
Weakness: CWE-502
Which versions are affected by CVE-2026-7818?
3 open source packages ship an affected version, including pgadmin4. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
pgadmin4 PyPI | All versions | 9.15 |
pgadmin4 PyPI | All versions | 9.15 |
pgadmin4 PyPI | All versions | 9.15 |
Products include Pgadmin Pgadmin 4.
How do I fix CVE-2026-7818?
Upgrade pgadmin4 to 9.15 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-7818 being exploited?
There is no known exploitation of CVE-2026-7818 in the wild and no public exploit code.
Other vulnerabilities in pgadmin.org pgAdmin 4
- CVE-2025-2945 pgAdmin 4: Remote Code Execution in Query Tool and Cloud Deployment
- CVE-2024-9014 OAuth2 client id and secret exposed through the web browser in pgAdmin 4
- CVE-2026-12046 Deserialization in pgAdmin 4
- CVE-2026-17351 SQL injection in pgAdmin 4
- CVE-2026-17566 Command injection in pgAdmin 4
Sources
Also known as GHSA-4rhg-h8f2-v4jm, PYSEC-2026-2865.