sevenz-rust2: unchecked 7z entry paths permit traversal and absolute-path file overwrites

sevenz-rust2 · Path traversal · CWE-22

Affectedsevenz-rust2

FixNo fix listed yet.

PublishedOct 30, 22:10 · GitHub_M

ScoredOct 30 · 6.1 · GitHub_M

Exploit code publicNone known · checked 21:18 UTC

ExploitedNone known · CISA KEV checked 22:05 UTC

What we know

No known exploitation. CISA KEV, checked 22:05 UTC.

No public exploit code known. Exploit-DB, Metasploit, Nuclei, checked 21:18 UTC.

An attacker needs local access to the machine. CVSS: local.

Someone has to open, click or run something first. CVSS: user interaction required.

A successful attack can change data. CVSS impact.

Description

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.

From GitHub_M

Affected and fixed versions

ProductAffectedFixed insevenz-rust2< 0.21.1–

Exploit code

Exploit-DBnone knownMetasploitnone knownNucleinone known

References

github.com/hasenbanck/sevenz-rust2/security/advisories/GHSA-qh76-45cr-8xrc · github.comrefsource_CONFIRM github.com/hasenbanck/sevenz-rust2/commit/ef760b61f3535ac8b93006212aef41bfebc237eb · github.comrefsource_MISC