nb-connect invalidly assumes the memory layout of std::net::SocketAddr

published 2021-02-14 5 y ago modified 2026-06-17 4 mo ago also GHSA-rm4w-6696-r77p , RUSTSEC-2021-0021 , EUVD-2021-1871

cvss: 9.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.4%; EPSS 1.4% chance of exploitation in 30 days, percentile 73%
public exploits: 0; none known

An issue was discovered in the nb-connect crate before 1.0.3 for Rust. It may have invalid memory access for certain versions of the standard library because it relies on a direct cast of std::net::SocketAddrV4 and std::net::SocketAddrV6 data structures.

Patch / fix

fixed in 2

crates.io nb-connect 1.0.3
nb-connect_project nb-connect 1.0.3

Exploit prediction

1.45% chance of exploitation in the next 30 days, higher than 73% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

rustsec.org https://rustsec.org/advisories/RUSTSEC-2021-0021.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P
GitHub	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
OSV	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
crates.io	nb-connect	<1.0.3 >=0.0.0-0, <1.0.3	1.0.3

Classification

Weakness

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

rustsec.org /advisories/RUSTSEC-2021-0021.html
web, exploit, third-party-advisory, advisory
nvd.nist.gov /vuln/detail/CVE-2021-27376
advisory
github.com /smol-rs/nb-connect/issues/1
web, report
github.com /smol-rs/nb-connect
package
crates.io /crates/nb-connect
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary