CVE-2021-3445

A flaw was found in libdnf's signature verification functionality in versions before 0.60.1. This flaw allows an attacker to achieve code execution if they can alter the header information of an RPM package and then trick a user or system into installing it. The highest risk of this vulnerability is to confidentiality, integrity, as well as system availability.

Published: 2021-05-19 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-3445 is rated Low Risk (33.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.04%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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

Exploit prediction scoring system (EPSS) score for CVE-2021-3445

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 2025-11-21 0.35% 0.04% -0.31%
2 2025-11-18 0.05% 0.35% +0.30%
3 2025-03-30 — 0.05% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3445

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big 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.
 1.6 5.9 [email protected]
5.1 2.0 MEDIUM
AV:N/AC:H/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:H)
Exploitation requires uncommon or highly specific conditions.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 4.9 6.4 [email protected]

Weakness enumeration for CVE-2021-3445

OS Trackers for CVE-2021-3445

vendor priority summary link
debian not yet assigned CVE-2021-3445 not yet assigned priority: Debian including 1 source packages (libdnf), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-3445
redhat medium — https://access.redhat.com/security/cve/CVE-2021-3445
suse medium CVE-2021-3445 severity moderate: SUSE including 35 source package names (dnf-4.7.0-4.el8, dnf-automatic-4.7.0-4.el8, …), 44 product×package rows across 5 product lines (SUSE Liberty Linux 8, SUSE Package Hub 15 SP4, … (5 product lines)): Fixed 44. https://www.suse.com/security/cve/CVE-2021-3445/
ubuntu medium CVE-2021-3445 medium priority: Ubuntu including 1 source packages (libdnf), 14 status rows across 14 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, trusty, upstream, xenial): DNE 5, ignored 5, not-affected 2, needs-triage 1, released 1. https://ubuntu.com/security/CVE-2021-3445

Affected software / configurations for CVE-2021-3445

Vendor Product Version Raw CPE
rpm libdnf < 0.60.1 cpe:2.3:a:rpm:libdnf:*:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*

References for CVE-2021-3445

cvelogic Threat Intelligence