How severe is CVE-2018-1000855?

CVE-2018-1000855 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-1000855 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1000855?

CVE-2018-1000855 affects Basecamp Easymon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-1000855?

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

When was CVE-2018-1000855 published?

CVE-2018-1000855 was published on 2018-12-20 and last updated on 2026-06-17.

CVE-2018-1000855

CVE-2018-1000855 is a medium-severity vulnerability in Basecamp Easymon with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Basecamp Easymon
Published: 2018-12-20
Last modified: 2026-06-17

Description

easymon version 1.4 and earlier contains a Cross Site Scripting (XSS) vulnerability in Endpoint where monitoring is mounted that can result in Reflected XSS that affects Firefox. Can be used to steal cookies, depending on the cookie settings.. This attack appear to be exploitable via The victim must click on a crafted URL that contains the XSS payload. This vulnerability appears to have been fixed in 1.4.1 and later.

Frequently asked questions

What is CVE-2018-1000855?: easymon version 1.4 and earlier contains a Cross Site Scripting (XSS) vulnerability in Endpoint where monitoring is mounted that can result in Reflected XSS that affects Firefox. Can be used to steal cookies, depending on the cookie settings.. This attack appear to be exploitable via The victim must click on a crafted URL that contains the XSS payload. This vulnerability appears to have been fixed in 1.4.1 and later.
How severe is CVE-2018-1000855?: CVE-2018-1000855 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-1000855 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1000855?: CVE-2018-1000855 affects Basecamp Easymon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-1000855?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-1000855 published?: CVE-2018-1000855 was published on 2018-12-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:basecamp:easymon:*:*:*:*:*:ruby:*:*

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