Critical File handling exploit reference

CVE-2026-54352 — Budibase Path Traversal via Symlinks in PWA Icon Upload

Budibase is an open-source low-code platform. Prior to 3.39.9, `POST /api/pwa/process-zip` at packages/server/src/api/routes/static.ts:24 accepts a builder-uploaded .zip, extracts it with extract-zip@2.0.1 into a temp directory, then for each entry listed in icons.json validates the icon path, opens it, and streams the bytes into MinIO. The resulting object is served back via GET /api/assets/{appId}/pwa/{uuid}.png. extract-zip@2.0.1 preserves absolute symlink targets when restoring symlink entries. The icon-source validator at packages/server/src/api/controllers/static/index.ts:259-268 resolves the icon source string against baseDir (path.resolve), checks resolvedSrc.startsWith(baseDir + path.sep) against that string, and calls fs.existsSync(resolvedSrc) which follows symbolic links to confirm the target exists. None of the three calls reject symbolic-link entries. packages/backend-core/src/objectStore/objectStore.ts:302 then calls (await fsp.open(path)).createReadStream() on the resolved path. fsp.open follows the symlink, the target file's bytes stream into MinIO, and the response of the asset-fetch endpoint returns those bytes verbatim. Result: a workspace-level builder reads any file the server process can open. This vulnerability is fixed in 3.39.9.

Published Jun 26, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.5% (30-day exploitation probability)+6
Technical severity (critical)+10
CISA SSVC: exploitation "poc"+5

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.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.49%

ahead of 41% of scored CVEs · Oct 14, 2026

Affects

Budibase

CVSS base

9.6

Critical · 2 source(s)

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.

Exploitation

Proof of concept

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

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 (Budibase Budibase).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
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
Budibase	Budibase	< 3.39.9	Vulnerable	NIST National Vulnerability Database
Budibase	Budibase	version < 3.39.9	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

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
9.6	CVSS 3.1	Critical	3.1	5.8	security-advisories@github.com via NIST National Vulnerability Database
9.6	CVSS 3.1	Critical	—	—	GitHub_M via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-22 · Path Traversal

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.49%

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 (../).

web/proxy/WAF logsnetwork IDS/IPSfile integrity (FIM)endpoint telemetry (EDR)

Analysis and videos

CVE-2026-54352: Budibase Path Traversal via Symlinks in PWA Icon Upload
Budibase versions before 3.39.9 let a workspace-level builder upload a .zip whose icon entries are symbolic links, causing the server to read files the server process can open and expose them through an asset endpoint. The record rates the issue critical (CVSS 3.1 base score 9.6) with high confidentiality and integrity impact. No KEV listing or confirmed exploitation appears in the sources consulted, and the record states the issue is fixed in 3.39.9.

Timeline

What happened to this CVE, newest first.

2026
Affected products added · budibase/budibase
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 9.6
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Jun 26, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

github.com/Budibase/budibase/security/advisories/GHSA-w7mq-r738-x278
Exploit, Vendor Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database

Elsewhere on this site

Budibase
every CVE for this vendor

File handling
same class

CWE-22
other pages naming this weakness

Related CVEs (same products)

High CVE-2026-54353 Budibase: Potential SSRF DNS rebinding bypass in outbound fetch validation Jun 26, 2026
Critical CVE-2026-54351 Budibase Mass Assignment in Webhook Trigger Enabling Cross-Workspace Automation Execution Jun 26, 2026
Critical CVE-2026-54350 Budibase: unauthenticated data read and write via PUBLIC app queries Jun 26, 2026
Critical CVE-2026-50137 Budibase Missing Authorization on S3 Upload URL Endpoint Jun 26, 2026
Medium CVE-2026-50136 Budibase: Unauthenticated S3 signed upload URL generation allows arbitrary writes with stored datasource credentials Jun 26, 2026
High CVE-2026-50132 Budibase: Chat Identity Link Hijacking via Missing Consent & CSRF — Account Impersonation in Budibase Jun 26, 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 fixed version, patch or mitigation documented.
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-2026-54352 is "Budibase Path Traversal via Symlinks in PWA Icon Upload", rated Critical. It affects Budibase (Budibase); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.6 describes technical severity. EPSS 0.49% 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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