Summary
### Summary The symbolic-link branch of `ZipArchive::extract_internal()` allocates a buffer using an attacker-declared size before reading any entry data. A 112-byte archive terminates the extracting process with `SIGABRT` through this infallible allocation. ### Details ```rust #[cfg(any(unix, windows))] if file.is_symlink() { let mut target = Vec::with_capacity(file.size() as usize); // @audit unbounded memory allocation file.read_to_end(&mut target)?; drop(file); make_symlink(&outpath, &target, &self.shared.files)?; continue; } ``` [`src/read/mod.rs#L399-L405`](https://github.com/zip-rs/zip2/blob/6f09b3064ec87c3a69ea9f3413f9f9638b4aa446/src/read/mod.rs#L399-L405) (reviewed commit `6f09b306`); the same code is at [`src/read.rs#L417-L418`](https://github.com/zip-rs/zip2/blob/v8.6.0/src/read.rs#L417-L418) in released v8.6.0. Both inputs are attacker-controlled: - [`ZipFile::size()`](https://github.com/zip-rs/zip2/blob/6f09b3064ec87c3a69ea9f3413f9f9638b4aa446/src/read/zipfile.rs#L243-L246) returns `uncompressed_size` verbatim from the central directory record. A ZIP64 extended-information extra field widens it to a full `u64` ([`src/read/mod.rs#L619-L625`](https://github.com/zip-rs/zip2/blob/6f09b3064ec87c3a69ea9f3413f9f9638b4aa446/src/read/mod.rs#L619-L625)). It is never cross-checked against the compressed size, the remaining archive length, or any platform-appropriate bound for a symlink target. - [`ZipFile::is_symlink()`](https://github.com/zip-rs/zip2/blob/6f09b3064ec87c3a69ea9f3413f9f9638b4aa446/src/read/zipfile.rs#L256-L260) is decided entirely by the central directory's external-attributes field, via the `S_IFLNK` bit. **Memory allocation failure → uncatchable process abort.** The reservation is sized from the declared `uncompressed_size` before a single byte of the entry is read. `Vec::with_capacity()` is infallible: on allocator refusal it calls `handle_alloc_error()`, which aborts the process. This is not a Rust panic — it is not caught by `catch_unwind()`…
Remediation
References
- Advisoryhttps://github.com/advisories/GHSA-q7v9-x93c-xqv3
- Referencehttps://github.com/zip-rs/zip2/security/advisories/GHSA-q7v9-x93c-xqv3
- Referencehttps://nvd.nist.gov/vuln/detail/CVE-2026-115909
- Referencehttps://github.com/zip-rs/zip2/pull/984
- Referencehttps://github.com/zip-rs/zip2/commit/a543a1fc8f3f3eef36f27bb137230295284cdb98
- Referencehttps://github.com/zip-rs/zip2/releases/tag/v9.0.0