CVE-2021-26078

Exp

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.

Published: 2021-06-07 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-26078 is rated High Exploit Risk (73.7/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 3.84%). 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +3.28% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-26078

EDB-ID Source Kind Published Link
50068 exploit_db edb 2021-06-28 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-26078

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.56% 3.84% +3.28%
2 2025-12-22 0.82% 0.56% -0.27%
3 2025-11-21 — 0.82% —

Full EPSS history (22 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-26078

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-26078

Affected software / configurations for CVE-2021-26078

Vendor Product Version Raw CPE
atlassian data_center < 8.5.14 cpe:2.3:a:atlassian:data_center:*:*:*:*:*:*:*:*
atlassian data_center >= 8.6.0, < 8.13.6 cpe:2.3:a:atlassian:data_center:*:*:*:*:*:*:*:*
atlassian data_center >= 8.14.0, < 8.16.1 cpe:2.3:a:atlassian:data_center:*:*:*:*:*:*:*:*
atlassian jira < 8.5.14 cpe:2.3:a:atlassian:jira:*:*:*:*:*:*:*:*
atlassian jira_server >= 8.6.0, < 8.13.6 cpe:2.3:a:atlassian:jira_server:*:*:*:*:*:*:*:*
atlassian jira_server >= 8.14.0, < 8.16.1 cpe:2.3:a:atlassian:jira_server:*:*:*:*:*:*:*:*

References for CVE-2021-26078

cvelogic Threat Intelligence