CVE-2020-28247

The lettre library through 0.10.0-alpha for Rust allows arbitrary sendmail option injection via transport/sendmail/mod.rs.

Published: 2020-11-12 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-28247 is rated Moderate Risk (47.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.50%). Core evidence: EPSS rose +1.24% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.

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-2020-28247

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 2026-06-15 0.26% 1.50% +1.24%
2 2025-03-30 0.23% 0.26% +0.03%
3 2025-03-29 0.23%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-28247

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]
5.0 2.0 MEDIUM
AV:N/AC:L/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: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:N)
No availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2020-28247

GitHub Security Advisory for CVE-2020-28247

Affected software / configurations for CVE-2020-28247

Vendor Product Version Raw CPE
lettre lettre >= 0.8.0, <= 0.8.3 cpe:2.3:a:lettre:lettre:*:*:*:*:*:*:*:*
lettre lettre >= 0.9.0, <= 0.9.5 cpe:2.3:a:lettre:lettre:*:*:*:*:*:*:*:*
lettre lettre 0.7.0 cpe:2.3:a:lettre:lettre:0.7.0:*:*:*:*:*:*:*
lettre lettre 0.10.0 cpe:2.3:a:lettre:lettre:0.10.0:alpha1:*:*:*:*:*:*
lettre lettre 0.10.0 cpe:2.3:a:lettre:lettre:0.10.0:alpha2:*:*:*:*:*:*
lettre lettre 0.10.0 cpe:2.3:a:lettre:lettre:0.10.0:alpha3:*:*:*:*:*:*

References for CVE-2020-28247

cvelogic Threat Intelligence