The vulnerability resides in SGLang’s replay_request_dump.py script, which performs insecure deserialization by calling pickle.load() on untrusted data without validation. An attacker that can supply a crafted .pkl file to the script can execute arbitrary code on the device running the script, leading to full compromise of confidentiality, integrity, and availability of the affected system. This weakness corresponds to the common weakness classification CWE-502 (Insecure Deserialization).

Affected vendor: SGLang. Product: SGLang, specifically the replay_request_dump.py script. No precise version information is provided in the CVE data, so any release that includes this script is potentially vulnerable.

The CVSS score of 7.8 indicates high severity. The EPSS score of less than 1% suggests low likelihood of exploitation in the near term, and the vulnerability is not listed in the CISA KEV catalog. Based on the description, the attack vector requires an attacker to get the malicious .pkl file processed by the script, which normally runs under the privileges of the user executing it. If the script is executed with elevated or privileged rights, the attacker can gain extensive system control. The exploit path is straightforward: supply a malicious pickle payload, invoke the script, and the payload’s code is executed during deserialization. The vulnerability can be prevented by removing the insecure load or ensuring only trusted data is deserialized.