CVE-2026-70558
Dinky Unauthenticated Arbitrary File Write via /download/uploadFromRsByLocal Gated Only by Hardcoded Default Token
Description
Dinky's POST /download/uploadFromRsByLocal handler passes the caller-supplied path parameter directly to new File(path) and file.transferTo(dest) with no path validation. The route is marked @SaIgnore and /download/** is excluded from the Sa-Token interceptor, so the only guard is a header equality check against a dinkyToken value whose default (efda1551-7958-4e0f-80a8-dfd107df3e38) is hardcoded in source and shipped to every deployment. Anyone who can reach Dinky's HTTP port (8888 by default) and supplies the hardcoded token can write arbitrary files as the Dinky service account. The default Docker image runs on 8888 with no proxy or authentication and chmod 777 on /opt/dinky, so the application's own classpath, launch scripts, and static assets are writable. Demonstrated impact: overwriting /opt/dinky/config/static/index.html served attacker JavaScript to admin browsers immediately, and writing /opt/dinky/org/dinky/Dinky.class executed attacker code as the Dinky service account at the next JVM start via a classpath-shadow launched by script/bin/auto.sh. Writes are uid 9999 (flink), not root, so /etc, /root, /home, and /usr are refused. Affects Dinky v1.2.5 (the current release) and the development branch, where the code is byte-identical.
INFO
Published Date :
Aug. 6, 2026, 10:18 p.m.
Last Modified :
Aug. 6, 2026, 10:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-70558
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 4.0 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Implement strict path validation for all file operations.
- Remove or secure the hardcoded dinkyToken value.
- Restrict file permissions for the Dinky service account.
- Update Dinky to a patched version when available.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-70558.
| URL | Resource |
|---|---|
| https://github.com/DataLinkDC/dinky | |
| https://github.com/DataLinkDC/dinky/issues/4566 | |
| https://github.com/DataLinkDC/dinky/security/advisories/GHSA-2p66-w3p3-5226 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-70558 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-70558
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-70558 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-70558 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 06, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'DataLinkDC', 'product': 'Dinky', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '1.2.5'}], 'defaultStatus': 'affected'}] Added Description Dinky's POST /download/uploadFromRsByLocal handler passes the caller-supplied path parameter directly to new File(path) and file.transferTo(dest) with no path validation. The route is marked @SaIgnore and /download/** is excluded from the Sa-Token interceptor, so the only guard is a header equality check against a dinkyToken value whose default (efda1551-7958-4e0f-80a8-dfd107df3e38) is hardcoded in source and shipped to every deployment. Anyone who can reach Dinky's HTTP port (8888 by default) and supplies the hardcoded token can write arbitrary files as the Dinky service account. The default Docker image runs on 8888 with no proxy or authentication and chmod 777 on /opt/dinky, so the application's own classpath, launch scripts, and static assets are writable. Demonstrated impact: overwriting /opt/dinky/config/static/index.html served attacker JavaScript to admin browsers immediately, and writing /opt/dinky/org/dinky/Dinky.class executed attacker code as the Dinky service account at the next JVM start via a classpath-shadow launched by script/bin/auto.sh. Writes are uid 9999 (flink), not root, so /etc, /root, /home, and /usr are refused. Affects Dinky v1.2.5 (the current release) and the development branch, where the code is byte-identical. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-434 Added Reference https://github.com/DataLinkDC/dinky Added Reference https://github.com/DataLinkDC/dinky/issues/4566 Added Reference https://github.com/DataLinkDC/dinky/security/advisories/GHSA-2p66-w3p3-5226