#VU20964 Use-after-free in libslirp - CVE-2019-15890

Vulnerability identifier: #VU20964

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-15890

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

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

Vendor: Freedesktop.org

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists in "ip_reass()" routine in "ip_input.c" file while reassembling incoming packets, if the first fragment is bigger than the m->m_dat[] buffer. A remote attacker can send a specially crafted packet and cause the application to crash.

Mitigation
Install update from vendor's website.

Vulnerable software versions

libslirp: 4.0.0

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External links
https://www.openwall.com/lists/oss-security/2019/09/06/3
https://gitlab.freedesktop.org/slirp/libslirp/commit/c5927943

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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.