CVE-2021-28876

Exp

In the standard library in Rust before 1.52.0, the Zip implementation has a panic safety issue. It calls __iterator_get_unchecked() more than once for the same index when the underlying iterator panics (in certain conditions). This bug could lead to a memory safety violation due to an unmet safety requirement for the TrustedRandomAccess trait.

Published: 2021-04-11 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-28876 is rated Exploit Available (57.6/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.42%). 1 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-2021-28876

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

Exploit prediction scoring system (EPSS) score for CVE-2021-28876

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 0.51% 0.42% -0.09%
2 2025-10-18 0.08% 0.51% +0.42%
3 2025-03-30 — 0.08% —

Full EPSS history (15 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-28876

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N 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:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-28876

OS Trackers for CVE-2021-28876

vendor priority summary link
alpine medium CVE-2021-28876: 1 source package rows (rust); 18 state rows across 6 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-community, edge-main); fixed 0, open 18. https://security.alpinelinux.org/vuln/CVE-2021-28876
debian not yet assigned CVE-2021-28876 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-2021-28876
gentoo normal CVE-2021-28876: 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-2021-28876
redhat medium — https://access.redhat.com/security/cve/CVE-2021-28876
suse high CVE-2021-28876 severity important: SUSE including 46 source package names (cargo, cargo-1.52.1-1.module+el8.4.0+11282+0729bac9, …), 151 product×package rows across 23 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 6, … (23 product lines)): Known Not Affected 137, Fixed 14. https://www.suse.com/security/cve/CVE-2021-28876/
ubuntu medium CVE-2021-28876 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-2021-28876

Affected software / configurations for CVE-2021-28876

Vendor Product Version Raw CPE
rust-lang rust < 1.52.0 cpe:2.3:a:rust-lang:rust:*:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

References for CVE-2021-28876

cvelogic Threat Intelligence