CVE-2026-84809
Tencent AI-Infra-Guard's skill-scan component excludes compiled Python bytecode files from analysis by hardcoding __pycache__ directories and .pyc/.pyo/.pyd extensions into skip lists across multiple scanning surfaces. Attackers can distribute skills with benign Python source files alongside malicious compiled bytecode that executes on import while the scanner reports a safe verdict, enabling code execution when operators install the skill.
What this means for your business
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 24% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 6.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N- CVSS v4
- 7.1
- Weakness
- CWE-693
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-02
- Last modified
- 2026-09-04
- Sources
- NVD
References
- https://github.com/Tencent/AI-Infra-Guard
- https://github.com/Tencent/AI-Infra-Guard/blob/v4.6.0/skill-scan/skill_scan/tools/dir/dir_actions.py
- https://github.com/Tencent/AI-Infra-Guard/blob/v4.6.0/skill-scan/skill_scan/utils/pre_scan.py
- https://github.com/Tencent/AI-Infra-Guard/commit/7e0f749e3c023e5c6ab7b32fe97b3f6f2e8aeb04
- https://github.com/Tencent/AI-Infra-Guard/issues/531
- https://www.vulncheck.com/advisories/tencent-ai-infra-guard-skill-scan-analysis-bypass-via-excluded-python-bytecode
- https://github.com/Tencent/AI-Infra-Guard/issues/531