{"id":"RUSTSEC-2026-0187","revision":"e8687f70d08b472f8c971644407581bb","records":[{"revision":"e8687f70d08b472f8c971644407581bb","observedAt":"2026-10-24T13:19:54.901+00:00","statement":{"source":"osv","id":"RUSTSEC-2026-0187","aliases":["GHSA-6fj4-rcr3-r7rr"],"title":"Stack overflow in lopdf via deeply nested PDF objects","description":"`lopdf::Document::load_mem` (and the other `load*` entry points) parses nested PDF arrays and dictionaries with unbounded recursion. A small crafted PDF whose Catalog contains a deeply nested array (`/X [[[ … ]]]`, on the order of 10,000 levels) exhausts the call stack and aborts the process with `SIGABRT`.\n\nBecause this is a stack-overflow abort rather than a `panic!`, it cannot be caught with `catch_unwind`: any service that parses untrusted PDF input with lopdf can be crashed by a ~21 KB file, resulting in a denial of service.\n\nConfirmed on lopdf 0.41.0 and earlier; fixed in 0.42.0. Default configuration, no features changed.\n\n## Proof of concept\n\n```rust\nfn main() {\n    let bytes = std::fs::read(\"poc.pdf\").unwrap(); // ~10,380-deep nested array in the Catalog\n    let _ = lopdf::Document::load_mem(&bytes);     // stack overflow -> SIGABRT\n}\n```\n\nAn equivalent PoC is a minimal PDF whose Catalog `/X` value is `\"[\" * 10380 + \"]\" * 10380`.\n\n## Suggested fix\n\nEnforce a maximum object-nesting depth in the parser and return an `Err` instead of recursing without bound.","state":0,"publishedAt":"2026-06-21T12:00:00+00:00","modifiedAt":"2026-10-17T15:15:02.5828976+00:00","affected":[{"ecosystem":"crates.io","name":"lopdf","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0.0.0-0"},{"kind":"fixed","version":"0.42.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":null,"severity":null}],"references":["https://crates.io/crates/lopdf","https://rustsec.org/advisories/RUSTSEC-2026-0187.html","https://github.com/J-F-Liu/lopdf/issues/502","https://github.com/J-F-Liu/lopdf/pull/503","https://github.com/J-F-Liu/lopdf/commit/c755394"],"sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0187","license":"OSV · upstream source license applies","key":"osv:RUSTSEC-2026-0187","identifiers":["RUSTSEC-2026-0187","GHSA-6fj4-rcr3-r7rr"]},"retained":false,"historicalAffected":[]}],"coverage":[]}