CVE-2026-94093
DLR-RM stable-baselines3 save_util.py VecNormalize.load deserialization
- State
- Published
- Severity
- 5.3 Medium
- Published
- Sep 20, 2026
- Updated
- Sep 21, 2026
- Reserved
- Sep 20, 2026
Description
A security vulnerability has been detected in DLR-RM stable-baselines3 up to 2.9.0. This affects the function PPO.load/load_replay_buffer/VecNormalize.load of the file save_util.py. Such manipulation leads to deserialization. It is possible to launch the attack remotely. The exploit has been disclosed publicly and may be used. In v2.9.0 the PyTorch tensor load path is hardened (weights_only=True), but that hardening was later reverted on master via PR #1913 "Hotfix: revert loading with weights_only=True" [blocked] to fix PyTorch 1.13 compat - so even the one "safe" path is inconsistent across versions. #2281 was closed as a duplicate of #1831 since both are unsafe pickle deserialization - but #1831's fix (PR #41) only gated the Hugging Face Hub loader in the separate huggingface_sb3 package. This finding covers the core stable_baselines3 load APIs (PPO.load, load_replay_buffer, VecNormalize.load), which have no safe mode or gate and remained exploitable in v2.9.0 until the outstanding hardening (PR #2264) ships.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.3 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P | VulDB |
| 3.1 | 6.3 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R | VulDB |
| 3.0 | 6.3 Medium | CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R | VulDB |
| 2.0 | 7.5 High | AV:N/AC:L/Au:N/C:P/I:P/A:P/E:POC/RL:ND/RC:UR | VulDB |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
stable-baselines3DLR-RM |
|
References
- VDB-408021 | DLR-RM stable-baselines3 save_util.py VecNormalize.load deserializationvdb-entrytechnical-description
- VDB-408021 | CTI Indicators (IOB, IOC, IOA)signaturepermissions-required
- CVE-2026-94093 | CVE Analysis and Reportthird-party-advisory
- Submit #952734 | DLR-RM stable-baselines3 v2.9.0 rcethird-party-advisory
- https://github.com/DLR-RM/stable-baselines3/issues/2281issue-tracking
- https://github.com/DLR-RM/stable-baselines3/product
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.