PT-2019-16422 · Rust · Chacha20 Crate

Published 2019-10-22 · Updated 2021-08-25 · CVE-2019-25005

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Name of the Vulnerable Software and Affected Versions chacha20 crate versions prior to 0.2.3

Description A ChaCha20 counter overflow issue makes it easier for attackers to determine plaintext. The ChaCha20 stream cipher can produce a maximum of 2^32 blocks before the 32-bit counter overflows. When this limit is exceeded, the keystream is duplicated, leading to failure modes similar to nonce reuse, which can expose the XOR of two plaintexts.

Recommendations For versions prior to 0.2.3, update to version 0.2.3 or later to resolve the issue, as this version now panics when the counter overflow occurs, preventing the exposure of the duplicated keystream.

Fix

Integer Overflow

Weakness Enumeration

CWE-190

Related Identifiers

CVE-2019-25005

GHSA-J2R6-2M5C-VGH5

RUSTSEC-2019-0029

Affected Products

Chacha20 Crate

References · 9

• https://osv.dev/vulnerability/GHSA-j2r6-2m5c-vgh5 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2019-25005 · Security Note
• https://osv.dev/vulnerability/CVE-2019-25005 · Vendor Advisory
• https://osv.dev/vulnerability/RUSTSEC-2019-0029 · Vendor Advisory
• https://github.com/RustCrypto/stream-ciphers/tree/master/chacha20 · Note
• https://github.com/RustCrypto/stream-ciphers/pull/64 · Note
• https://t.me/cvenotify/8218 · Telegram Post
• https://rustsec.org/advisories/RUSTSEC-2019-0029.html · Note
• https://crates.io/crates/chacha20 · Note