MEDIUM
CVE-2021-26081
NVD-CWE-noinfoPublished: July 20, 2021· Updated: Jun 17, 2026
5.3
CVSS v3.1
Official Description
REST API in Atlassian Jira Server and Jira Data Center before version 8.5.14, from version 8.6.0 before 8.13.6, and from version 8.14.0 before 8.16.1 allows remote attackers to enumerate usernames via a Sensitive Data Exposure vulnerability in the `/rest/api/latest/user/avatar/temporary` endpoint.
Technical Analysis
CVE-2021-26081 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityLow
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Affected Vendors & Products
Atlassian4 product(s)
data centerjirajira data centerjira server
Source: NVD CPE · 4 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (2)
→
https://jira.atlassian.com/browse/JRASERVER-72499Patch · Vendor Advisory
→
https://jira.atlassian.com/browse/JRASERVER-72499Patch · Vendor Advisory
Quick Facts
CVE IDCVE-2021-26081
CVSS Score5.3 / 10
SeverityMEDIUM
WeaknessNVD-CWE-noinfo
CISA KEVNo
Affected1 vendor(s)
PublishedJul 20, 2021
Related CVEs (NVD-CWE-noinfo)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-26081 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.