{"cve":"CVE-2026-107717","nvd":{"published":"2026-10-08T22:17:27.560","modified":"2026-10-13T17:17:16.860","status":"Deferred","description":"Banks generates meaningful LLM prompts using a simple template language. Prior to 2.5.0, Banks Prompt.chat_messages() attempts to parse every line of rendered template output as ChatMessage JSON. When an application renders untrusted data and passes the returned ChatMessage objects to an LLM provider, attacker-controlled JSON can cross the prompt boundary and become a system, assistant, or tool message because ChatMessage.role accepts arbitrary strings. This can override application instructions, alter the intended prompt structure, or confuse downstream tool and message handling. This issue is fixed in version 2.5.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","score":6.5},"cwes":["CWE-20"],"references":["https://github.com/masci/banks/commit/02172b816fb84f6a824cc09a8aca7416f53c12cb","https://github.com/masci/banks/pull/78","https://github.com/masci/banks/releases/tag/v2.5.0","https://github.com/masci/banks/security/advisories/GHSA-hmq2-7hp6-7crh","https://github.com/masci/banks/security/advisories/GHSA-hmq2-7hp6-7crh"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:58:01.639778232+00:00"},"epss":{"cve":"CVE-2026-107717","score":0.00335,"percentile":0.26674,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-hmq2-7hp6-7crh","url":"https://osv.dev/vulnerability/GHSA-hmq2-7hp6-7crh","summary":"Banks: User-controlled prompt input can be parsed as privileged chat messages","modified":"2026-10-15T14:56:15.712699415Z","packages":[{"ecosystem":"PyPI","name":"banks","purl":"pkg:pypi/banks","ranges":["<2.5.0"],"fixed":["2.5.0"]}]},{"id":"PYSEC-2026-4202","url":"https://osv.dev/vulnerability/PYSEC-2026-4202","summary":"Banks: User-controlled prompt input can be parsed as privileged chat messages","modified":"2026-10-15T14:45:07.348589881Z","packages":[{"ecosystem":"PyPI","name":"banks","purl":"pkg:pypi/banks","ranges":["<2.5.0"],"fixed":["2.5.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}