#VU18403 Integer overflow in Python - CVE-2018-20406

Vulnerability identifier: #VU18403

Vulnerability risk: Low

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-20406

CWE-ID: CWE-190

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Python
Universal components / Libraries / Scripting languages

Vendor: Python.org

Description

The vulnerability allows a remote attacker to perform denial of service (DoS) attack.

The vulnerability exists due to integer overflow in modules/_pickle.c when processing a large LONG_BINPUT value during the "resize to twice the size" attempt. A remote attacker can supply overly large data, trigger integer overflow and exhaust all resources on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Python: 3.6.0 - 3.6.8, 3.7.0

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External links
https://bugs.python.org/issue34656
https://github.com/python/cpython/commit/a4ae828ee416a66d8c7bf5ee71d653c2cc6a26dd
https://lists.debian.org/debian-lts-announce/2019/02/msg00011.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/D3LXPABKVLFYUHRYJPM3CSS5MS6FXKS7/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ICBEGRHIPHWPG2VGYS6R4EVKVUUF4AQW/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JSKPGPZQNTAULHW4UH63KGOOUIDE4RRB/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TR6GCO3WTV4D5L23WTCBF275VE6BVNI3/
https://security.netapp.com/advisory/ntap-20190416-0010/

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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.