CHANGING Inc. NHIServiSignAdapter Windows Versions - Heap Overflow

published 2020-12-31 5y ago modified 2026-06-17 4mo ago also EUVD-2020-18476

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 2.0%; EPSS 2.0% chance of exploitation in 30 days, percentile 80%
public exploits: 0; none known

NHIServiSignAdapter fails to verify the length of digital credential files’ path which leads to a heap overflow loophole. Remote attackers can use the leak to execute code without privilege.

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Exploit prediction

1.98% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

CHANGING Inc. NHIServiSignAdapter

Classification

Weakness

CWE-122 Heap-based Buffer Overflow
CWE-787 Out-of-bounds Write

References

twcert.org.tw /tw/cp-132-4271-951cd-1.html
third-party-advisory

Sources

CVE List CVE-2020-25843
NVD CVE-2020-25843

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