CVE-2026-86861 — pgAdmin 4: File Manager save_file writes through a symbolic link planted after the containment check
pgAdmin 4's File Manager save_file endpoint, which backs saving from the Query Tool and ERD, validated the requested path with Filemanager.check_access_permission() and then opened the file for writing with a plain open() call. CVE-2026-7819 had previously hardened the separate file upload path by opening its target with O_NOFOLLOW, so that the kernel refuses to follow a symbolic link at the final path component, but save_file was left on an unprotected open(). A symbolic link already present when the check ran was rejected by the check itself; the remaining exposure was a link substituted at the final path component in the interval between the check and the write, at which point the write followed the link and landed outside the user's storage directory, creating or overwriting an arbitrary file as the operating-system account running pgAdmin. Exploitation requires the ability to create or replace a symbolic link inside the requesting user's storage directory. pgAdmin exposes no interface that creates symbolic links, so this requires filesystem access to the pgAdmin host or to a shared or network-mounted storage backend, together with winning the timing window. The reporter did not achieve a write against a released version, having attempted approximately 63,000 racing requests without success; the reported defect is the uncovered write path rather than a demonstrated sandbox escape. The fix routes save_file's write through the same O_NOFOLLOW-protected helper already used by the upload path, so both File Manager write sinks carry identical kernel-enforced protection, and reports a symbolic-link refusal explicitly instead of surfacing the underlying system error text. Note that files created by save_file are now given mode 0600, inheriting the behaviour introduced for uploads. The protection covers the final path component; substitution of an intermediate directory component is not addressed by this change. This issue affects pgAdmin 4: from the introduction of the containment check in the File Manager save path before 9.18.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.3% (30-day exploitation probability)+4
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Pgadmin Pgadmin 4, Pgadmin.org pgAdmin 4).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (file handling), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Pgadmin | Pgadmin 4 | < 9.18 | Vulnerable | NIST National Vulnerability Database |
| Pgadmin.org | pgAdmin 4 | < 9.18 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 6.0 | CVSS 4.0 | Medium | — | — | f86ef6dc-4d3a-42ad-8f28-e6d5547a5007 via NIST National Vulnerability Database |
| 6.0 | CVSS 4.0 | Medium | — | — | PostgreSQL via CVE Program (cve.org) e CISA ADP |
| 5.9 | CVSS 3.1 | Medium | 1.6 | 4.2 | f86ef6dc-4d3a-42ad-8f28-e6d5547a5007 via NIST National Vulnerability Database |
| 5.9 | CVSS 3.1 | Medium | — | — | PostgreSQL via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L (score shown at the top: f86ef6dc-4d3a-42ad-8f28-e6d5547a5007) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Monitor file creation in web directories and paths with traversal sequences (../).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · pgadmin.org/pgadmin 4
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 5.9
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
1 on the record
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-86864 pgAdmin 4: Argument and connection-string injection via the database field in the Backup tool 28d
- Medium CVE-2026-86862 pgAdmin 4: Connection-string injection via the database field in the Restore and Maintenance tools 28d
- Critical CVE-2026-86863 pgAdmin 4: Authentication bypass via a client-controlled identity header in Webserver authentication mode 28d
- Critical CVE-2026-17566 pgAdmin 4: RCE via backslash-escape mismatch in Import/Export Data query guard (incomplete defense, sibling gap to CVE-2025-13780) Jul 31, 2026
- Medium CVE-2026-17348 pgAdmin 4: Missing authentication decorator on Constraints, preferences, Debugger and Schema Diff routes allows unauthenticated access in SERVER mode (incomplete fix for CVE-2026-12046) Jul 31, 2026
- High CVE-2026-17347 pgAdmin 4: OS command injection in MASTER_PASSWORD_HOOK via untrusted username substitution Jul 31, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-86861 is "pgAdmin 4: File Manager save_file writes through a symbolic link planted after the containment check", rated Medium. It affects Pgadmin 4 (Pgadmin); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.9 describes technical severity. EPSS 0.32% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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