CVE-2021-39885

Exp

A Stored XSS in merge request creation page in all versions of Gitlab EE starting from 13.7 before 14.1.7, all versions starting from 14.2 before 14.2.5, and all versions starting from 14.3 before 14.3.1 allows an attacker to execute arbitrary JavaScript code on the victim's behalf via malicious approval rule names

Published: 2021-10-04 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-39885 is rated High Exploit Risk (70.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.95%). 2 public exploit reference(s) are indexed (Exploit-DB). 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-2021-39885

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-39885

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 0.22% 0.95% +0.73%
2 2025-10-15 0.36% 0.22% -0.14%
3 2025-10-07 — 0.36% —

Full EPSS history (15 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-39885

CVSS metrics for this CVE.

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]
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/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: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: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.
 2.3 2.7 [email protected]
3.5 2.0 LOW
AV:N/AC:M/Au:S/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:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 6.8 2.9 [email protected]

Weakness enumeration for CVE-2021-39885

OS Trackers for CVE-2021-39885

vendor priority summary link
debian unimportant CVE-2021-39885 unimportant priority: Debian including 1 source packages (gitlab), 1 status rows across 1 suites (sid): resolved 1. https://security-tracker.debian.org/tracker/CVE-2021-39885
ubuntu medium CVE-2021-39885 medium priority: Ubuntu including 1 source packages (gitlab), 12 status rows across 12 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, trusty, upstream, xenial): DNE 10, ignored 1, needs-triage 1. https://ubuntu.com/security/CVE-2021-39885

Affected software / configurations for CVE-2021-39885

Vendor Product Version Raw CPE
gitlab gitlab >= 13.7.0, < 14.1.7 cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*
gitlab gitlab >= 14.2.0, < 14.2.5 cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*
gitlab gitlab 14.3.0 cpe:2.3:a:gitlab:gitlab:14.3.0:*:*:*:enterprise:*:*:*

References for CVE-2021-39885

URL Tags
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39885.json Vendor Advisory
https://gitlab.com/gitlab-org/gitlab/-/issues/341140 Exploit Issue Tracking Vendor Advisory
https://hackerone.com/reports/1342009 Exploit Permissions Required Third Party Advisory
cvelogic Threat Intelligence