CVE-2026-61725
sevenz-rust2: unchecked 7z entry paths permit traversal and absolute-path file overwrites
What happened?
sevenz-rust2 is a Rust-native 7z compressor and `decompress`or. Prior to 0.21.1, extracting an attacker-supplied 7z archive can write or overwrite files outside the destination directory. In `src/util/decompress.rs`, `decompress_impl` computes each destination with `dest.join(entry.name())` without normalizing the archive's UTF-16 entry name or verifying containment, and `default_entry_extract_fn` writes to it with `File::create`. Parent-directory components escape the extraction root, and an absolute entry path makes the join discard the destination entirely. The convenience entry points `decompress`, `decompress_file`, `decompress_with_password`, and `decompress_file_with_password` all use this default path. Overwriting writable configuration, startup, cron, or build files can lead to code execution or persistence. The archive bytes are the attacker-controlled trust boundary, including for applications that automatically unpack uploaded or otherwise untrusted archives. This issue is fixed in version 0.21.1.
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| sevenz-rust2hasenbanck | affected: < 0.21.1 | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.