Deserialization in Pgadmin 4
CVE-2026-7818
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.
Vulnerability class: Insecure Deserialization
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (27.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.004 · change: +0.002
Affected products
- Pgadmin 4
- Pgadmin.org Pgadmin 4 — versions 0
Weakness classification (CWE)
References
- f86ef6dc-4d3a-42ad-8f28-e6d5547a5007 (issue-tracking, Patch, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-7818?
- CVE-2026-7818 is a high-severity vulnerability in Pgadmin 4, classified under Deserialization of Untrusted Data. CVSS score: 7.0/10. Published 2026-05-11.
- How severe is CVE-2026-7818?
- High severity. CVSS v3 base score is 7.0 out of 10.