CVE-2025-61765
python-socketio vulnerable to arbitrary Python code execution (RCE) through malicious pickle deserialization in certain multi-server deployments
Impact
### Summary A remote code execution vulnerability in python-socketio versions prior to 5.14.0 allows attackers to execute arbitrary Python code through malicious pickle deserialization in multi-server deployments on which the attacker previously gained access to the message queue that the servers use for internal communications. ### Details When Socket.IO servers are configured to use a message queue backend such as Redis for inter-server communication, messages sent between the servers are encoded using the `pickle` Python module. When a server receives one of these messages through the message queue, it assumes it is trusted and immediately deserializes it. The vulnerability stems from deserialization of messages using Python's `pickle.loads()` function. Having previously obtained access to the message queue, the attacker can send a python-socketio server a crafted pickle payload that executes arbitrary code during deserialization via Python's `__reduce__` method. ### Impact This vulnerability only affects deployments with a compromised message queue. The attack can lead to the attacker executing random code in the context of, and with the privileges of a Socket.IO server process. Single-server systems that do not use a message queue, and multi-server systems with a secure message queue are not vulnerable. ### Remediation In addition to making sure standard security practices are followed in the deployment of the message queue, users of the python-socketio package can upgrade to version 5.14.0 or newer, which remove the `pickle` module and use the much safer JSON encoding for inter-server messaging.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | python-socketio | >= 0.8.0, < 5.14.0 | 5.14.0 |
Affected products
| Product | Affected versions |
|---|---|
| Python-Socketio | before 5.14.0 |
Versions were read from the advisory text. No structured product data has been published for this record yet.
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/miguelgrinberg/python-socketio/commit/53f6be094257ed81476b0e212c8cddd6d06ca39a
- https://github.com/miguelgrinberg/python-socketio/security/advisories/GHSA-g8c6-8fjj-2r4m
- https://www.bluerock.io/post/cve-2025-61765-bluerock-discovers-critical-rce-in-socket-io-ecosystem
- https://github.com/advisories/GHSA-g8c6-8fjj-2r4m
- https://nvd.nist.gov/vuln/detail/CVE-2025-61765