How severe is CVE-2020-28247?

CVE-2020-28247 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-28247 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-28247?

CVE-2020-28247 primarily affects Lettre. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-28247?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-28247 published?

CVE-2020-28247 was published on 2020-11-12 and last updated on 2026-06-17.

CVE-2020-28247

CVE-2020-28247 is a medium-severity vulnerability in Lettre with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Lettre
Published: 2020-11-12
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2020-28247?: The lettre library through 0.10.0-alpha for Rust allows arbitrary sendmail option injection via transport/sendmail/mod.rs.
How severe is CVE-2020-28247?: CVE-2020-28247 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-28247 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-28247?: CVE-2020-28247 primarily affects Lettre. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-28247?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-28247 published?: CVE-2020-28247 was published on 2020-11-12 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:lettre:lettre:*:*:*:*:*:*:*:*
cpe:2.3:a:lettre:lettre:0.7.0:*:*:*:*:*:*:*
cpe:2.3:a:lettre:lettre:0.10.0:alpha1:*:*:*:*:*:*
cpe:2.3:a:lettre:lettre:0.10.0:alpha2:*:*:*:*:*:*
cpe:2.3:a:lettre:lettre:0.10.0:alpha3:*:*:*:*:*:*

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