Cygwin versions 1.7.2 up to and including 1.8.0 are vulnerable to buffer overflow vulnerability in wcsxfrm/wcsxfrm_l functions resulting in…

published 2017-07-21 9 y ago modified 2026-06-17 4 mo ago also EUVD-2017-16540

cvss: 7.5; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.7%; EPSS 2.7% chance of exploitation in 30 days, percentile 86%
public exploits: 0; none known

Cygwin versions 1.7.2 up to and including 1.8.0 are vulnerable to buffer overflow vulnerability in wcsxfrm/wcsxfrm_l functions resulting into denial-of-service by crashing the process or potential hijack of the process running with administrative privileges triggered by specially crafted input string.

Exploit prediction

2.75% chance of exploitation in the next 30 days, higher than 86% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

cygwin.com https://cygwin.com/ml/cygwin/2017-05/msg00149.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

Red Hat, Inc. cygwin

Classification

Weakness

CWE-787 Out-of-bounds Write
CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

cygwin.com /ml/cygwin/2017-05/msg00149.html
exploit, mailing-list, vendor-advisory

Sources

CVE List CVE-2017-7523
NVD CVE-2017-7523

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary