Security

ZCode: Zhipu apologizes after secret code upload

3 min read

TL;DR Too Long; Didn’t read

The Chinese AI provider Zhipu apologized on September 18, 2026, for a security vulnerability in its coding tool ZCode, which uploaded complete user repositories unnoticed to its own cloud. Affected were source code, access data, and Git histories, in one case over 32,900 files. Zhipu disabled the function, had the storage deleted, and released ZCode as an open-source project.

A suitcase full of source-code slips, keys, and padlocks gets sucked into a storm cloud bearing a Zhipu logo sticker, with one broken padlock lying beside it. Image generated with GPT Image 2

Key takeaways

  • ZCode packaged entire workspaces including Git history and automatically uploaded them to Alibaba Cloud.
  • Users could not open the encrypted packages themselves because the private key was solely with Zhipu.
  • Taiyuan Chengming Tech sent Zhipu a twelve-page legal notice regarding a project with over 32,000 files.
  • Zhipu disabled the upload function in ZCode version 3.14.0 and removed the repo wiki function.
  • The security service provider NSFOCUS confirmed the complete deletion of the affected cloud storage.
  • Zhipu subsequently released ZCode completely as an open-source project on GitHub.

The Chinese AI provider Zhipu has apologized for a security vulnerability in its coding assistant ZCode: The tool uploaded complete developer workspaces unnoticed to the company’s own cloud. An affected company reported a single project with more than 32,900 files and around 411 million text characters – independently unverified. Zhipu has since disabled the function and disclosed the code.

Encryption Excludes Users From Their Own Data

The security researcher ferstar discovered the behavior on September 18, 2026, when he wanted to free up space on his MacBook, and published his analysis on the same day. ZCode had packed entire workspaces: complete Git directories, commit histories, LFS caches for binary files, and global program settings across multiple projects. A test project with 313 megabytes of compressed size contained 42,411 files alone, with the Git portion accounting for about 87 percent of the data package according to the analysis.

ZCode encrypted the packages with AES-256, while the necessary symmetric key was enclosed by RSA encryption. Problematic: the public RSA key was delivered anew by the Zhipu server with each connection, while the corresponding private key remained solely there. Users could not open their own data packages, often several hundred megabytes in size, on their own hard drives. The researcher interpreted this as an indication that the function was not a backup for users, but primarily served Zhipu itself – especially since the upload occurred independently of the settings in the program interface.

The company Taiyuan Chengming Tech sent Zhipu a twelve-page legal notice after, according to its own statements, one of its projects was affected with around 32,900 files and about 411 million text characters – the exact number could not be independently verified. The company demands information about where the data was stored, whether it crossed national borders, and whether third parties or model training accessed it. Additionally, the company requests complete proof of deletion from servers, caches, and backup systems.

Similar incidents with AI coding tools are increasing: just at the beginning of September, the security company Air Security uncovered a vulnerability in four AI coding agents with Plugin4Shell, through which unverified code could be injected. The ZCode case runs in the opposite direction: here, not malicious commands flowed into the tool, but user data flowed out of it, all without the need for separate consent – a pattern that an analysis of SpaceXAI’s coding agent Grok Build had already exposed in July. Both cases show how little users of AI coding agents can currently control what is actually happening in the background. Security teams are now increasingly examining the network traffic of such tools instead of relying solely on manufacturer information.

Zhipu Closes the Gap and Opens the Code

Zhipu responded on September 18 with an initial statement, explaining that the function was officially intended for codebase indexing, for example for history recovery and the knowledge function Repo Wiki. With version 3.14.0, the company completely removed Repo Wiki and disabled the upload path. The security service provider NSFOCUS and the state-run China Academy of Information and Communications Technology subsequently confirmed independently that the affected storage area at Alibaba Cloud had been completely cleared.

Additionally, Zhipu published the complete source code of ZCode on GitHub – the tool has since been available for free download and viewing, even in Germany and the EU, eliminating a fixed rollout date for individual countries. A separate paid version has not yet been announced. For its own AI platform, Zhipu also announced new controls that allow users to exclude permanent storage of their inputs and outputs during standard model calls. Exceptions remain, according to company statements, for batch requests, file uploads, and data that must be retained for legal or security reasons.

It remains open whether the promised zero-data confirmation also applies to copies in backup and disaster recovery systems, which Taiyuan Chengming explicitly wants proven. It will also be crucial whether the now disclosed codebase withstands independent audits or whether similar upload mechanisms in other AI coding tools have so far only gone undetected.

Frequently asked questions

Is ZCode still safe to use after the incident?

Zhipu removed the upload function with version 3.14.0 and disclosed the code; a deletion confirmation is available according to NSFOCUS, but a residual risk cannot be definitively ruled out from a single audit.

What does ZCode cost and where is it available?

ZCode is available for free as an open-source project on GitHub, also for users in Germany and the EU; a paid additional version is not known so far.

What data was specifically affected?

According to a damaged company, source code, access data, database passwords, and personal information from Git directories were among the uploaded contents.

How does this case differ from the Plugin4Shell vulnerability?

Plugin4Shell allowed the injection of malicious code via prepared checksums, while ZCode sent user data externally without consent – two different attack vectors in AI coding tools.

Is an independent body reviewing the disclosed code?

According to Zhipu, the China Academy of Information and Communications Technology and NSFOCUS have already reviewed the incident; the disclosure on GitHub now opens the code for further independent audits.

Sources (4)
  1. ZCode: Silently Uploading Your Entire Git History to the Cloud (ferstar.org)
  2. zai-org/ZCode (GitHub)
  3. Taiyuan Chengming Tech sends Zhipu legal notice (KuCoin News)
  4. Zhipu open-sources ZCode after data dispute, plans no-retention controls for MaaS (TechNode)

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