How severe is CVE-2016-4842?

CVE-2016-4842 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 low, integrity none, and availability none.

Is CVE-2016-4842 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4842?

CVE-2016-4842 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-2016-4842?

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

When was CVE-2016-4842 published?

CVE-2016-4842 was published on 2017-04-20 and last updated on 2026-06-17.

CVE-2016-4842

CVE-2016-4842 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Cybozu Mailwise
Published: 2017-04-20
Last modified: 2026-06-17

Description

Cybozu Mailwise before 5.4.0 allows remote attackers to obtain information on when an email is read.

Frequently asked questions

What is CVE-2016-4842?: Cybozu Mailwise before 5.4.0 allows remote attackers to obtain information on when an email is read.
How severe is CVE-2016-4842?: CVE-2016-4842 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 low, integrity none, and availability none.
Is CVE-2016-4842 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4842?: CVE-2016-4842 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-2016-4842?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-4842 published?: CVE-2016-4842 was published on 2017-04-20 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

CVE-2014-5314 — Critical (CVSS 9.0): Buffer overflow in Cybozu Office 9 and 10 before 10.1.0, Mailwise 4 and 5 before 5.1.4, and Dezie 8 before 8.1.1 allows…
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CVE-2013-2305 — Medium (CVSS 6.8): Cross-site request forgery (CSRF) vulnerability in Cybozu Office before 8.1.6 and 9.x before 9.3.0, Cybozu Dezie before…
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CVE-2018-0559 — Medium (CVSS 6.1): Cross-site scripting vulnerability in Cybozu Mailwise 5.0.0 to 5.4.1 allows remote attackers to inject arbitrary web…
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