Out-of-bounds read in opencc - #VU128159
Published: April 27, 2026
Vulnerability identifier: #VU128159
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: N/A
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: opencc.byvoid.com
Affected software:
opencc
opencc
Detailed vulnerability description
The vulnerability allows a remote attacker to disclose sensitive information and cause a denial of service.
The vulnerability exists due to out-of-bounds read in UTF-8 processing in MaxMatchSegmentation::Segment and Conversion::Convert(const char*) when processing malformed or truncated UTF-8 input. A remote attacker can send specially crafted UTF-8 input to disclose sensitive information and cause a denial of service.
In some cases, adjacent heap bytes may be propagated into the conversion result.
Remediation
Install security update from vendor's website.