How severe is CVE-2016-4841?

CVE-2016-4841 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2016-4841 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4841?

CVE-2016-4841 primarily affects Cybozu Mailwise. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-4841?

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

When was CVE-2016-4841 published?

CVE-2016-4841 was published on 2017-04-21 and last updated on 2026-06-17.

CVE-2016-4841

CVE-2016-4841 is a medium-severity vulnerability in Cybozu Mailwise with a CVSS 3.x base score of 4.3. 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: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cybozu Mailwise
Published: 2017-04-21
Last modified: 2026-06-17

Description

Cybozu Mailwise before 5.4.0 allows remote attackers to inject arbitrary email headers.

Frequently asked questions

What is CVE-2016-4841?: Cybozu Mailwise before 5.4.0 allows remote attackers to inject arbitrary email headers.
How severe is CVE-2016-4841?: CVE-2016-4841 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2016-4841 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4841?: CVE-2016-4841 primarily affects Cybozu Mailwise. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-4841?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-4841 published?: CVE-2016-4841 was published on 2017-04-21 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:a:cybozu:mailwise:5.0.0:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.0.4:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.0.5:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.0.6:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.1.0:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.1.1:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.1.2:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.1.4:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.2.0:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.2.1:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.3.0:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.3.1:*:*:*:*:*:*:*
cpe:2.3:a:cybozu:mailwise:5.3.2:*:*:*:*:*:*:*

More vulnerabilities in Cybozu Mailwise

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