CVE-2024-21686 [High] | XSS in Confluence Data Center

This High severity Stored XSS vulnerability was introduced in versions 7.13 of Confluence Data Center and Server. This Stored XSS vulnerability, with a CVSS Score of 7.3, allows an authenticated attacker to execute arbitrary HTML or JavaScript code on a victims browser which has high impact to confidentiality, high impact to integrity, no impact to availability, and requires user interaction. Atlassian recommends that Confluence Data Center and Server customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions listed on this CVE See the release notes (https://confluence.atlassian.com/doc/confluence-release-notes-327.html). You can download the latest version of Confluence Data Center and Server from the download center (https://www.atlassian.com/software/confluence/download-archives). This vulnerability was reported via our Bug Bounty program.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-04-27	3.33%	2.57%	-0.76%
2	2026-03-25	2.88%	3.33%	+0.44%
3	2025-12-05	—	2.88%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-04-27

3.33%

2.57%

-0.76%

2026-03-25

2.88%

3.33%

+0.44%

2025-12-05

—

2.88%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.7	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/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:L) A normal user session is enough; they don’t have to be admin. 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:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:N) Service keeps running; no real outage angle.	2.3	5.8	[email protected]
7.3	3.0	HIGH	`CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/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:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:N) Service keeps running; no real outage angle.	2.1	5.2	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.7

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/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:L): A normal user session is enough; they don’t have to be admin.
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:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N): Service keeps running; no real outage angle.

2.3

5.8

[email protected]

7.3

3.0

HIGH

CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/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:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N): Service keeps running; no real outage angle.

2.1

5.2

[email protected]

Affected software / configurations for CVE-2024-21686

Vendor	Product	Version	Raw CPE
atlassian	confluence_data_center	< 7.19.22	cpe:2.3:a:atlassian:confluence_data_center::::::::
atlassian	confluence_data_center	>= 7.20.0, < 8.5.9	cpe:2.3:a:atlassian:confluence_data_center::::::::
atlassian	confluence_data_center	>= 8.6.0, < 8.9.1	cpe:2.3:a:atlassian:confluence_data_center::::::::
atlassian	confluence_server	< 7.19.22	cpe:2.3:a:atlassian:confluence_server::::::::
atlassian	confluence_server	>= 7.20.0, < 8.5.9	cpe:2.3:a:atlassian:confluence_server::::::::

References for CVE-2024-21686

URL	Tags
https://confluence.atlassian.com/pages/viewpage.action?pageId=1417150917	Vendor Advisory
https://jira.atlassian.com/browse/CONFSERVER-96134	Issue Tracking

URL

CVE-2024-21686

Exploit prediction scoring system (EPSS) score for CVE-2024-21686

Common vulnerability scoring system (CVSS) metrics for CVE-2024-21686

Weakness enumeration for CVE-2024-21686

Affected software / configurations for CVE-2024-21686

References for CVE-2024-21686