CVE-2016-4340 Auth bypass in n/a
Remote authenticated users can impersonate any other user in GitLab, leading to account takeover.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2016-4340?
CVE-2016-4340 is a high-severity authentication bypass vulnerability in Gitlab Gitlab, published on 23 Jan 2017. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The impersonate feature in Gitlab 8.7.0, 8.6.0 through 8.6.7, 8.5.0 through 8.5.11, 8.4.0 through 8.4.9, 8.3.0 through 8.3.8, and 8.2.0 through 8.2.4 allows remote authenticated users to "log in" as any other user via unspecified vectors.
Weakness: CWE-264
Which versions are affected by CVE-2016-4340?
It affects 1 product.
Products include Gitlab Gitlab.
How do I fix CVE-2016-4340?
No fix has been published for CVE-2016-4340 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2016-4340 being exploited?
There is no known exploitation of CVE-2016-4340 in the wild and no public exploit code.
Public exploit code: 1 Exploit-DB entry.
Other vulnerabilities in Gitlab Gitlab
- CVE-2026-97229 GitLab Community Edition and Enterprise Edition Integer Overflow or Wraparound
- CVE-2026-85706 GitLab Community Edition and Enterprise Edition Path Traversal
- CVE-2023-7028 GitLab Community and Enterprise Editions Improper Access Control
- CVE-2021-22205 GitLab Community and Enterprise Editions Remote Code Execution
- CVE-2021-39935 GitLab Community and Enterprise Editions Server-Side Request Forgery (SSRF)
Sources
Also known as GHSA-rxh8-jh3g-ccqq, UBUNTU-CVE-2016-4340.