Vulnerability · Published Jun 10, 2026 · Assigned by GitHub_M

CVE-2026-46702Russh: Post-decompression SSH packet size was not bounded, allowing remote oversized compressed packets

High 7.5

In plain English

A high-severity resource allocation without limits in russh from Eugeny. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.3%top 81.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Russh is a Rust SSH client & server library. From version 0.34.0 to before version 0.61.1, when SSH compression is enabled, russh accepted compressed packets whose on-wire size passed the normal transport packet-length checks but whose decompressed size was much larger. This allowed a remote peer to send oversized post-decompression packets that should have been rejected. In current releases, this is a remote denial-of-service / resource-exhaustion issue in the post-decompression receive path. In older releases before 0.58.0, the same remote decompression path used CryptoVec, which appears to make the historical impact worse. This issue has been patched in version 0.61.1.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:14rust-russh0.64.1-1DEBIAN-CVE-2026-46702

Affected products (as reported)

VendorProductVersions
Eugeny russh >= 0.34.0, < 0.61.1

Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References