How severe is CVE-2021-26078?

CVE-2021-26078 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-2021-26078 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26078?

CVE-2021-26078 primarily affects Atlassian Data Center. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26078?

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

When was CVE-2021-26078 published?

CVE-2021-26078 was published on 2021-06-07 and last updated on 2026-06-17.

CVE-2021-26078

CVE-2021-26078 is a medium-severity vulnerability in Atlassian Data Center 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: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Atlassian Data Center
Published: 2021-06-07
Last modified: 2026-06-17

Description

The number range searcher component in Jira Server and Jira Data Center before version 8.5.14, from version 8.6.0 before version 8.13.6, and from version 8.14.0 before version 8.16.1 allows remote attackers inject arbitrary HTML or JavaScript via a cross site scripting (XSS) vulnerability.

Frequently asked questions

What is CVE-2021-26078?: The number range searcher component in Jira Server and Jira Data Center before version 8.5.14, from version 8.6.0 before version 8.13.6, and from version 8.14.0 before version 8.16.1 allows remote attackers inject arbitrary HTML or JavaScript via a cross site scripting (XSS) vulnerability.
How severe is CVE-2021-26078?: CVE-2021-26078 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-2021-26078 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26078?: CVE-2021-26078 primarily affects Atlassian Data Center. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26078?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26078 published?: CVE-2021-26078 was published on 2021-06-07 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:atlassian:data_center:*:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:jira:*:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:jira_server:*:*:*:*:*:*:*:*

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