CVE-2017-1000373

Severity: medium (CVSS 6.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 13.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2017-06-19 · updated 2026-06-17
Weakness: CWE-400

Description

The OpenBSD qsort() function is recursive, and not randomized, an attacker can construct a pathological input array of N elements that causes qsort() to deterministically recurse N/4 times. This allows attackers to consume arbitrary amounts of stack memory and manipulate stack memory to assist in arbitrary code execution attacks. This affects OpenBSD 6.1 and possibly earlier versions.

Affected products

OpenBSD: through 6.1

References

http://www.securityfocus.com/bid/99177
http://www.securitytracker.com/id/1039427
https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdlib/qsort.c?rev=1.15&content-type=text/x-cvsweb-markup
https://support.apple.com/HT208112
https://support.apple.com/HT208113
https://support.apple.com/HT208115
https://support.apple.com/HT208144
https://www.exploit-db.com/exploits/42271/
https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
http://www.securityfocus.com/bid/99177
http://www.securitytracker.com/id/1039427
https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdlib/qsort.c?rev=1.15&content-type=text/x-cvsweb-markup

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