#VU19504 OS Command Injection in Patch - CVE-2019-13638

Vulnerability identifier: #VU19504

Vulnerability risk: Low

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-13638

CWE-ID: CWE-78

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Patch
Server applications / File servers (FTP/HTTP)

Vendor: GNU

Description

The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.

The vulnerability exists due to insufficient validation of ed style diff payload with shell metacharacters in patch files. A remote attacker can trick the victim to use a specially crafted patch file and execute arbitrary OS commands.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Patch: 2.7.0 - 2.7.6

---

External links
https://git.savannah.gnu.org/cgit/patch.git/commit/?id=3fcd042d26d70856e826a42b5f93dc4854d80bf0
https://security-tracker.debian.org/tracker/CVE-2019-13638
https://www.debian.org/security/2019/dsa-4489

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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