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.

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History

Mon, 11 May 2026 16:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-502
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Mon, 11 May 2026 15:30:00 +0000

Type Values Removed Values Added
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.
Title pgAdmin 4: Unsafe deserialization (CWE-502) in file-backed session manager leads to remote code execution
References
Metrics cvssV3_1

{'score': 7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 7.3, 'vector': 'CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: PostgreSQL

Published:

Updated: 2026-05-11T16:07:11.650Z

Reserved: 2026-05-04T21:26:59.607Z

Link: CVE-2026-7818

cve-icon Vulnrichment

Updated: 2026-05-11T16:07:01.350Z

cve-icon NVD

Status : Received

Published: 2026-05-11T16:17:38.847

Modified: 2026-05-11T16:17:38.847

Link: CVE-2026-7818

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses