{"data":{"id":"c1c741c8-acb7-4de2-80f8-8601e80bd48b","title":"Coding Agents Propagate Vulnerabilities in Code Bases","summary":"This research study examines whether vulnerabilities already present in a codebase cause coding agents to write similar vulnerabilities in new code. Across 96 backend tasks and 20 pairs of real C/C++ repository tasks focused on memory safety, insecure existing code made agents write vulnerable code more often, with a 3.4% average reduction in correct and secure backend implementations and a 35.4% average gap between secure and insecure C/C++ contexts. Security-focused prompting did not stop the propagation, and agents attributed their choices to existing code in 76.5% of cases even though they recognized the vulnerability in 69.9%.","solution":"N/A -- no mitigation discussed in source.","labels":["security","research"],"sourceUrl":"https://arxiv.org/abs/2611.11455v1","publishedAt":"2026-11-08T15:35:45.000Z","cveId":null,"cweIds":null,"cvssScore":null,"cvssSeverity":null,"severity":"info","attackType":[],"issueType":"research","affectedPackages":null,"affectedPackageNames":null,"affectedPackageRefs":null,"affectedVendors":[],"affectedVendorsRaw":["LLM-based coding agents"],"classifierModel":"claude-haiku-5-5","classifierPromptVersion":"v4","summaryPromptVersion":"v2","headline":null,"headlinePromptVersion":null,"cvssVector":null,"attackVector":null,"attackComplexity":null,"privilegesRequired":null,"userInteraction":null,"exploitMaturity":null,"epssScore":null,"epssCheckedAt":null,"kevDateAdded":null,"advisoryAliases":null,"affectedPackagesSource":null,"affectedPackagesCheckedAt":null,"patchAvailable":null,"disclosureDate":"2026-11-08T15:35:45.000Z","fixReleasedAt":null,"daysToFix":null,"fixCheckedAt":null,"capecIds":null,"crossRefCount":0,"attackSophistication":"moderate","impactType":["integrity"],"aiComponentTargeted":"agent","llmSpecific":true,"classifierConfidence":0.9,"researchCategory":"preprint","atlasIds":null}}