# PYSEC-2026-1: A single post-release of dydx-v4-client contained obfuscated multi-stage loader

> A compromised PyPI account uploaded a malicious version of dydx-v4-client containing an obfuscated loader that executes arbitrary code on the host system.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Jan 2026

## What is PYSEC-2026-1?

PYSEC-2026-1 is a vulnerability in dydx-v4-client, published on 28 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A PyPI user account compromised by an attacker and was able to
upload a malicious version (1.1.5.post1) of the `dydx-v4-client` package.
This version contains a highly obfuscated multi-stage loader
that ultimately executes malicious code on the host system.

While the final payload is not visible because it is tucked away inside 100 layers of encoding, 
the structural design—specifically the use of recursive decompression followed by an `exec()` call
is a definitive indicator of malicious software,
likely a "Crypter" or "Dropper" masquerading as a cryptocurrency-related utility.
with the intent on connecting to hxxps://dydx.priceoracle.site/py
to download and execute further payloads.

Users of the `dydx-v4-client` package should immediately uninstall version 1.1.5.post1
and revert to the last known good version (1.1.5) or later secure versions once available.
Additionally, users should monitor their systems for any unusual activity
and consider running security scans to detect any potential compromise.

## Which versions are affected by PYSEC-2026-1?

1 open source package ship an affected version, including dydx-v4-client.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `dydx-v4-client` | PyPI | All versions | None |

## How do I fix PYSEC-2026-1?

No fix has been published for PYSEC-2026-1 yet. Limit exposure of the affected software until one is available.

## Is PYSEC-2026-1 being exploited?

There is no known exploitation of PYSEC-2026-1 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for PYSEC-2026-1 and fix it if it is affected.

What it is: PYSEC-2026-1 is a vulnerability in dydx-v4-client, published on 28 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of PYSEC-2026-1 in the wild and no public exploit code.

Affected packages and fixed versions:
- dydx-v4-client (PyPI): affected all versions; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/PYSEC-2026-1/ (Markdown: https://insights.sbomify.com/PYSEC-2026-1/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/PYSEC-2026-1

---
From sbomify Insights: https://insights.sbomify.com/PYSEC-2026-1/
Summaries are generated and may contain mistakes; the official description above is the record.