How severe is CVE-2017-9801?

CVE-2017-9801 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2017-9801 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-9801?

CVE-2017-9801 primarily affects Apache Commons Email. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-9801?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2017-9801 published?

CVE-2017-9801 was published on 2017-08-07 and last updated on 2026-06-17.

CVE-2017-9801

CVE-2017-9801 is a high-severity vulnerability in Apache Commons Email with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apache Commons Email
Published: 2017-08-07
Last modified: 2026-06-17

Description

When a call-site passes a subject for an email that contains line-breaks in Apache Commons Email 1.0 through 1.4, the caller can add arbitrary SMTP headers.

Frequently asked questions

What is CVE-2017-9801?: When a call-site passes a subject for an email that contains line-breaks in Apache Commons Email 1.0 through 1.4, the caller can add arbitrary SMTP headers.
How severe is CVE-2017-9801?: CVE-2017-9801 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2017-9801 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-9801?: CVE-2017-9801 primarily affects Apache Commons Email. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-9801?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2017-9801 published?: CVE-2017-9801 was published on 2017-08-07 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:a:apache:commons_email:1.0:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.3.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.3.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.3.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:commons_email:1.4:*:*:*:*:*:*:*

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