CVE-2017-17969

Severity: high (CVSS 7.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 5.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-01-30 · updated 2026-06-17
Weakness: CWE-787

Description

Heap-based buffer overflow in the NCompress::NShrink::CDecoder::CodeReal method in 7-Zip before 18.00 and p7zip allows remote attackers to cause a denial of service (out-of-bounds write) or potentially execute arbitrary code via a crafted ZIP archive.

Affected products

7-Zip: before 18.00 — fixed in 18.00
7-Zip P7Zip: before 18.0 — fixed in 18.0
Debian Linux: 7.0, 8.0, 9.0

How to fix

Upgrade to a fixed version: 7-Zip 18.00; 7-Zip P7Zip 18.0. Check the vendor advisory for mitigations.

References

http://www.securitytracker.com/id/1040831
https://0patch.blogspot.si/2018/02/two-interesting-micropatches-for-7-zip.html
https://github.com/p7zip-project/p7zip/issues/7
https://landave.io/2018/01/7-zip-multiple-memory-corruptions-via-rar-and-zip/
https://lists.debian.org/debian-lts-announce/2018/02/msg00003.html
https://usn.ubuntu.com/3913-1/
https://www.debian.org/security/2018/dsa-4104
http://www.securitytracker.com/id/1040831
https://0patch.blogspot.si/2018/02/two-interesting-micropatches-for-7-zip.html
https://landave.io/2018/01/7-zip-multiple-memory-corruptions-via-rar-and-zip/
https://lists.debian.org/debian-lts-announce/2018/02/msg00003.html
https://usn.ubuntu.com/3913-1/

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