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{"bugzilla": {"description": "nltk: NLTK: Resource poisoning via improper package archive extraction", "id": "2512413", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2512413"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N", "status": "draft"}, "cwe": "CWE-367", "details": ["A flaw was found in the `nltk.downloader` component of NLTK. This vulnerability allows for cross-package resource and model poisoning. The downloader extracts package archives into shared namespaces and only validates package integrity after extraction. This design flaw enables one package to overwrite another package's trusted resources, leading to an integrity compromise that can affect machine learning pipelines and reproducibility-sensitive environments."], "name": "CVE-2026-12261", "package_state": [{"cpe": "cpe:/a:redhat:exploit_intelligence:0", "fix_state": "Out of support scope", "package_name": "exploit-intelligence-tech-preview/vulnerability-analysis-rhel9", "product_name": "Exploit Intelligence"}, {"cpe": "cpe:/a:redhat:lightspeed_core", "fix_state": "Fix deferred", "package_name": "lightspeed-core/lightspeed-stack-rhel9", "product_name": "Lightspeed Core"}, {"cpe": "cpe:/a:redhat:lightspeed_core", "fix_state": "Fix deferred", "package_name": "lightspeed-core/rag-tool-cpu-rhel9", "product_name": "Lightspeed Core"}, {"cpe": "cpe:/a:redhat:lightspeed_core", "fix_state": "Fix deferred", "package_name": "lightspeed-core/rag-tool-cuda-12.9-rhel9", "product_name": "Lightspeed Core"}, {"cpe": "cpe:/a:redhat:openshift_lightspeed", "fix_state": "Fix deferred", "package_name": "openshift-lightspeed/lightspeed-ocp-rag-rhel9", "product_name": "OpenShift Lightspeed"}, {"cpe": "cpe:/a:redhat:openshift_lightspeed", "fix_state": "Fix deferred", "package_name": "openshift-lightspeed/lightspeed-service-api-rhel9", "product_name": "OpenShift Lightspeed"}, {"cpe": "cpe:/a:redhat:openshift_lightspeed", "fix_state": "Fix deferred", "package_name": "openshift-lightspeed-tech-preview/lightspeed-rag-tool-rhel9", "product_name": "OpenShift Lightspeed"}, {"cpe": "cpe:/a:redhat:ansible_automation_platform:2", "fix_state": "Out of support scope", "package_name": "ansible-automation-platform-25/lightspeed-chatbot-rhel8", "product_name": "Red Hat Ansible Automation Platform 2"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-llama-stack-core-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-pipeline-runtime-pytorch-llmcompressor-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-ta-lmes-job-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-trustyai-garak-lls-provider-dsp-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-trustyai-nemo-guardrails-server-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-workbench-jupyter-pytorch-llmcompressor-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}], "public_date": "2026-08-07T06:25:10Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-12261\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-12261\nhttps://huntr.com/bounties/8b8c381e-08a8-4e4f-bb46-a320c96a364f"], "statement": "This Moderate impact vulnerability in NLTK's downloader component allows for cross-package resource poisoning. By extracting package archives into shared namespaces before integrity validation, an attacker could, indirectly, overwrite trusted resources, compromising data integrity in machine learning pipelines and affecting reproducibility-sensitive environments. Exploitation requires user interaction and has high attack complexity.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "nltk/nltk", "source": "cna", "vendor": "nltk"}, "product": "nltk/nltk", "vendor": "nltk"}], "created": "2026-08-07T07:30:09.506164+00:00", "updated": "2026-08-08T02:00:13.406495+00:00", "vendors": ["nltk", "nltk$PRODUCT$nltk/nltk"]}