Local code execution via unsafe model deserialization
Published Apr 16, 2025 · Updated Apr 21, 2025
Deserialization in LMSYS Org FastChat 0.2.0 through 0.2.36 allows local users to execute code via crafted PyTorch model files. The split_files and apply_delta_low_cpu_mem functions call torch.load on base and delta files without weights_only=True, permitting pickle payloads to instantiate executable objects. Exploitation requires low-privileged local access and control of a model file that FastChat subsequently loads; code runs in the FastChat process context.
Summary
What happened
Deserialization in LMSYS Org FastChat 0.2.0 through 0.2.36 allows local users to execute code via crafted PyTorch model files. The split_files and apply_delta_low_cpu_mem functions call torch.load on base and delta files without weights_only=True, permitting pickle payloads to instantiate executable objects. Exploitation requires low-privileged local access and control of a model file that FastChat subsequently loads; code runs in the FastChat process context.
The record
- CVE
- CVE-2025-3677
- Published
- Apr 16, 2025
- Updated
- Apr 21, 2025
- Vendor
- LMSYS Org
- Product
- FastChat
- Classifications
- CWE-20, CWE-502, T1203
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 16, 2025CVE publishedPublication date reported by the CVE source.
- Apr 21, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0.2.0
- Affected versionversion=0.2.1
- Affected versionversion=0.2.10
- Affected versionversion=0.2.11
- Affected versionversion=0.2.12
- Affected versionversion=0.2.13
- Affected versionversion=0.2.14
- Affected versionversion=0.2.15
- Affected versionversion=0.2.16
- Affected versionversion=0.2.17
- Affected versionversion=0.2.18
- Affected versionversion=0.2.19
- Affected versionversion=0.2.2
- Affected versionversion=0.2.20
- Affected versionversion=0.2.21
- Affected versionversion=0.2.22
- Affected versionversion=0.2.23
- Affected versionversion=0.2.24
- Affected versionversion=0.2.25
- Affected versionversion=0.2.26
- Affected versionversion=0.2.27
- Affected versionversion=0.2.28
- Affected versionversion=0.2.29
- Affected versionversion=0.2.3
- Affected versionversion=0.2.30
- Affected versionversion=0.2.31
- Affected versionversion=0.2.32
- Affected versionversion=0.2.33
- Affected versionversion=0.2.34
- Affected versionversion=0.2.35
- Affected versionversion=0.2.36
- Affected versionversion=0.2.4
- Affected versionversion=0.2.5
- Affected versionversion=0.2.6
- Affected versionversion=0.2.7
- Affected versionversion=0.2.8
- Affected versionversion=0.2.9
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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