# CVE-2026-19761: DTStack Taier path traversal in file upload controller

Source: https://junglewise.ai/threats/cve-2026-19761-dtstack-taier-path-traversal-in-file-upload-controller  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-14. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-19761 · Severity: medium · CVSS 4.7 · Published 2026-08-14

Taier is a big data development platform used for data job submission, scheduling, and monitoring. A path traversal vulnerability in the file upload functionality allows attackers to write files outside the intended directory, potentially overwriting system files or injecting malicious content into the application.

Technologies: [DTStack Taier](https://junglewise.ai/threats/technologies/taier). Vendors: [DTStack](https://junglewise.ai/threats/vendors/dtstack).

## Quick answers

**Is CVE-2026-19761 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-19761 being exploited in the wild.

**How severe is CVE-2026-19761?** Medium severity, with a CVSS score of 4.7, published 14 August 2026.

**Which products and versions are affected?** DTStack Taier 1.4.0.

**Is there a fix for CVE-2026-19761?** A patch was published on 2026-08-14: Fixed in version 1.5.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-19761 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-19761?** Check whether you run DTStack Taier at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a path traversal flaw in the UploadController.java component, specifically in the MultipartFile.getOriginalFilename function. The File parameter is not properly validated, allowing an attacker to craft a malicious filename with path traversal sequences (e.g., ../) to write files to arbitrary locations on the filesystem. The attack is remotely exploitable and does not require authentication. An attacker can exploit this to overwrite critical files, inject code, or cause service disruption. The issue was patched in version 1.5.0 with commit 572773c, which added proper path validation to the file upload handler.

## Affected products

- DTStack Taier 1.4.0

## Timeline

- 2026-08-14: disclosed
- 2026-08-14: patched: Fixed in version 1.5.0

## References

- [https://github.com/DTStack/Taier/](https://github.com/DTStack/Taier/)
- [https://github.com/DTStack/Taier/commit/572773c4315e23e51e30115151cb091749a8d03e](https://github.com/DTStack/Taier/commit/572773c4315e23e51e30115151cb091749a8d03e)

## Related threats

- [DTStack Taier path traversal in cluster creation](https://junglewise.ai/threats/cve-2026-19763-dtstack-taier-path-traversal-in-cluster-creation)
- [DTStack Taier path traversal in chunk upload endpoint](https://junglewise.ai/threats/cve-2026-19762-dtstack-taier-path-traversal-in-chunk-upload-endpoint)
- [DTStack Taier authentication bypass in LoginInterceptor](https://junglewise.ai/threats/cve-2026-11618-dtstack-taier-authentication-bypass-in-logininterceptor)
- [DTStack Taier OS command injection in REST API](https://junglewise.ai/threats/cve-2026-9437-dtstack-taier-os-command-injection-in-rest-api)