CVE-2026-73289RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-beta.12, RustFS evaluates the ForAllValues: and ForAnyValue: set qualifiers with the negated string operators StringNotEquals, StringNotEqualsIgnoreCase, StringNotLike, ArnNotEquals, and ArnNotLike using each other's semantics because crates/policy/src/policy/function/string.rs negates the aggregate result after eval or eval_like instead of negating each request-value predicate before quantification. Partially overlapping policy and request value sets can therefore make an Allow condition grant access to an excluded principal or make a Deny guardrail fail, including policies based on jwt:groups and jwt:roles; absent keys also receive the opposite ForAllValues: and ForAnyValue: behavior. This issue is fixed in version 1.0.0-beta.12.