Privilege escalation in Bundler

1) Files or Directories Accessible to External Parties

EUVDB-ID: #VU49352

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-3881

CWE-ID: CWE-552 - Files or Directories Accessible to External Parties

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to Bundler uses a predictable path in /tmp/, created with insecure permissions as a storage location for gems, if locations under the user's home directory are not available. If Bundler is used in a scenario where the user does not have a writable home directory, an attacker could place malicious code in this directory that would be later loaded and executed.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

bundler: 1.0.0 rc1 - 2.0.2

CPE2.3

• cpe:2.3:a:bundler:bundler:1.0.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:bundler:bundler:1.0.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:bundler:bundler:1.0.0:rc3:*:*:*:*:*:*

External links

https://bugzilla.redhat.com/show_bug.cgi?id=1651826

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.