CVE-2021-29922

Exp

library/std/src/net/parser.rs in Rust before 1.53.0 does not properly consider extraneous zero characters at the beginning of an IP address string, which (in some situations) allows attackers to bypass access control that is based on IP addresses, because of unexpected octal interpretation.

Published: 2021-08-07 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-29922 is rated High Exploit Risk (70.8/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 0.33%). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-29922

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-29922

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-05 0.18% 0.33% +0.15%
2 2025-11-21 2.04% 0.18% -1.86%
3 2025-11-18 — 2.04% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-29922

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.2 [email protected]
6.4 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 4.9 [email protected]

Weakness enumeration for CVE-2021-29922

OS Trackers for CVE-2021-29922

vendor priority summary link
alpine critical CVE-2021-29922: 1 source package rows (rust); 28 state rows across 8 repos (3.17-community, 3.18-community, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-community, edge-main); fixed 8, open 20. https://security.alpinelinux.org/vuln/CVE-2021-29922
debian not yet assigned CVE-2021-29922 not yet assigned priority: Debian including 1 source packages (rustc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2021-29922
gentoo normal CVE-2021-29922: 1 GLSA(s) (202210-09), 2 atom(s) (dev-lang/rust, dev-lang/rust-bin); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-29922
redhat medium — https://access.redhat.com/security/cve/CVE-2021-29922
suse high CVE-2021-29922 severity important: SUSE including 47 source package names (cargo, cargo-1.54.0-2.module+el8.5.0+12254+dc27bae9, …), 158 product×package rows across 23 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 6, … (23 product lines)): Known Not Affected 143, Fixed 15. https://www.suse.com/security/cve/CVE-2021-29922/
ubuntu medium CVE-2021-29922 medium priority: Ubuntu including 1 source packages (rustc), 16 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 4, not-affected 4, DNE 3, released 3, needed 2. https://ubuntu.com/security/CVE-2021-29922

Affected software / configurations for CVE-2021-29922

Vendor Product Version Raw CPE
rust-lang rust < 1.53.0 cpe:2.3:a:rust-lang:rust:*:*:*:*:*:*:*:*

References for CVE-2021-29922

cvelogic Threat Intelligence