CVE-2026-9856

{"id": "CVE-2026-9856", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-9856", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-03T14:57:31.978427Z"}}], "cvssMetricV30": [{"type": "Secondary", "source": "security@huntr.dev", "cvssData": {"scope": "UNCHANGED", "version": "3.0", "baseScore": 7.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 4.2, "exploitabilityScore": 2.8}]}, "affected": [{"source": "security@huntr.dev", "affectedData": [{"vendor": "huggingface", "product": "huggingface/transformers", "versions": [{"status": "affected", "version": "unspecified", "lessThan": "5.10.0", "versionType": "custom"}]}]}], "published": "2026-08-02T16:16:25.413", "references": [{"url": "https://github.com/huggingface/transformers/commit/eaaaf8494dd5386634ae37d1d122212fdc315be5", "source": "security@huntr.dev"}, {"url": "https://huntr.com/bounties/362824d5-fe18-40e8-a6cf-62277f97a170", "source": "security@huntr.dev"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "security@huntr.dev", "description": [{"lang": "en", "value": "CWE-22"}]}], "descriptions": [{"lang": "en", "value": "A vulnerability in huggingface/transformers versions <=5.8.0.dev0 allows an attacker to perform arbitrary file writes via path traversal. The issue resides in the `save_pretrained()` methods of `PreTrainedTokenizerBase` and `ProcessorMixin`, where keys from the `chat_template` dictionary are used directly as filenames without proper validation. An attacker can exploit this by publishing a malicious Hugging Face Hub repository with a crafted `tokenizer_config.json` file. When a victim downloads and saves the tokenizer or processor, the attacker-controlled keys can escape the intended save directory, enabling arbitrary file writes with attacker-controlled content. This vulnerability affects multiple processors inheriting from `ProcessorMixin`, including Idefics, Florence, Gemma, Phi, and Qwen-VL."}, {"lang": "es", "value": "Una vulnerabilidad en las versiones menor o igual que 5.8.0.dev0 de huggingface/transformers permite a un atacante realizar escrituras de archivos arbitrarias mediante salto de ruta. El problema reside en los m\u00e9todos \u2019save_pretrained()\u2019 de \u2019PreTrainedTokenizerBase\u2019 y \u2019ProcessorMixin\u2019, donde las claves del diccionario \u2019chat_template\u2019 se utilizan directamente como nombres de archivo sin una validaci\u00f3n adecuada. Un atacante puede explotar esto publicando un repositorio malicioso en Hugging Face Hub con un archivo \u2019tokenizer_config.json\u2019 manipulado. Cuando una v\u00edctima descarga y guarda el tokenizador o procesador, las claves controladas por el atacante pueden escapar del directorio de guardado previsto, permitiendo escrituras de archivos arbitrarias con contenido controlado por el atacante. Esta vulnerabilidad afecta a m\u00faltiples procesadores que heredan de \u2019ProcessorMixin\u2019, incluyendo Idefics, Florence, Gemma, Phi y Qwen-VL."}], "lastModified": "2026-10-23T22:10:00.160", "sourceIdentifier": "security@huntr.dev"}