#VU15583 Double free error in gettext - CVE-2018-18751

Vulnerability identifier: #VU15583

Vulnerability risk: Low

CVSSv4.0: 5.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2018-18751

CWE-ID: CWE-415

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
gettext
Universal components / Libraries / Libraries used by multiple products

Vendor: GNU

Description

The vulnerability allows a local attacker to cause DoS condition on the target system.

The vulnerability exists due to a double-free condition that exists in the default_add_messagefunction, as defined in the read-catalog.c source code file that is related to an invalid-free condition in the po_gram_parse function, in the po-gram-gen.ysource code file. A local attacker can execute the msgfmt --check command on a file that submits malicious input and cause the service to crash.

Mitigation
Cybersecurity Help is currently unaware of any solutions addressing the vulnerability.

Vulnerable software versions

gettext: 0.19.8 - 0.19.8.1

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External links
https://github.com/CCCCCrash/POCs/tree/master/Bin/Tools-gettext-0.19.8.1/doublefree
https://github.com/CCCCCrash/POCs/tree/master/Bin/Tools-gettext-0.19.8.1/heapcorruption

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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. However, proof of concept for this vulnerability is available.