CVE-2025-15536: Opencc Open Chinese Convert Has Out-of-bounds Vulnerability

LOW
Advisory Identifier: GHSA-5pr6-crvp-2j9f
Share
CVSS 5.3
CWE-787 CWE-119
Published
Advisory Summary

CVE-2025-15536 is a LOW (CVSS 5.3) open chinese convert has out-of-bounds vulnerability (CWE-787: Out-of-bounds Write) affecting Opencc libraries in the npm ecosystem. The issue involves open chinese convert has out-of-bounds write. Remediation is available by upgrading affected packages to version 1.2.0.

CVE-2025-15536 at a Glance

CVE Identifier CVE-2025-15536
GHSA Identifier GHSA-5pr6-crvp-2j9f
Severity LOW
CVSS v3.1 Base Score 5.3
CWE Classification CWE-787: Out-of-bounds Write
Affected Product Opencc
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L).

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2025-15536

To remediate this vulnerability, upgrade all affected Opencc dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

opencc fixed: 1.2.0 
npm install opencc@1.2.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls opencc

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2025-15536, inspect your project dependencies using npm:

npm ls opencc

Analyze the terminal output to locate any version of Opencc in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.2.0), your application is affected.

Note: The npm ls opencc command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-787: Out-of-bounds Write, where the product writes data past the end, or before the beginning, of the intended buffer. In Opencc, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A weakness has been identified in BYVoid OpenCC up to 1.1.9. This vulnerability affects the function opencc::MaxMatchSegmentation of the file src/MaxMatchSegmentation.cpp. This manipulation causes heap-based buffer overflow. The attack is restricted to local execution. The exploit has been made available to the public and could be used for attacks. Patch name: 345c9a50ab07018f1b4439776bad78a0d40778ec. To fix this issue, it is recommended to deploy a patch.

CVE-2025-15536 Affected Opencc Versions

1 component(s)
Fixed Versions:
1.2.0
Product / Package Ecosystem Affected Versions Fixed Version
opencc
npm/opencc
npm
< 1.2.0
1.2.0

References

NVD — CVE-2025-15536 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-15536
Opencc Source Repository REPOSITORY
https://github.com/BYVoid/OpenCC/issues/997
Opencc Source Repository REPOSITORY
https://github.com/BYVoid/OpenCC/pull/1005
Security Fix Commit FIX COMMIT
https://github.com/BYVoid/OpenCC/commit/345c9a50ab07018f1b4439776bad78a0d40778ec
Opencc Source Repository REPOSITORY
https://github.com/BYVoid/OpenCC
Opencc Source Repository REPOSITORY
https://github.com/oneafter/1222/blob/main/repro
vuldb.com/ WEB
https://vuldb.com/?ctiid.341708
vuldb.com/ WEB
https://vuldb.com/?id.341708
vuldb.com/ WEB
https://vuldb.com/?submit.733347

Frequently Asked Questions

What is CVE-2025-15536?
CVE-2025-15536 is a security vulnerability in Opencc involving Open Chinese Convert has Out-of-bounds Write under CWE-787: Out-of-bounds Write.
Which Opencc versions are affected?
Affected versions include releases prior to 1.2.0 across affected packages: opencc.
What version fixes CVE-2025-15536?
Upgrading to 1.2.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is opencc affected?
Yes, opencc is affected in releases prior to 1.2.0. Upgrade your dependency to 1.2.0 or later.
What is the CVSS score of CVE-2025-15536?
CVE-2025-15536 has a CVSS v3.1 base score of 5.3 (LOW) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.
What CWE is associated with CVE-2025-15536?
CVE-2025-15536 is classified under CWE-787: Out-of-bounds Write (The product writes data past the end, or before the beginning, of the intended buffer.).
How can I check npm dependencies for CVE-2025-15536?
Run the dependency tree command: 'npm ls opencc'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-5pr6-crvp-2j9f",
  "modified" : "2026-02-06T22:32:12Z",
  "published" : "2026-01-18T09:30:27Z",
  "aliases" : [ "CVE-2025-15536" ],
  "summary" : "Open Chinese Convert has Out-of-bounds Write",
  "details" : "A weakness has been identified in BYVoid OpenCC up to 1.1.9. This vulnerability affects the function opencc::MaxMatchSegmentation of the file src/MaxMatchSegmentation.cpp. This manipulation causes heap-based buffer overflow. The attack is restricted to local execution. The exploit has been made available to the public and could be used for attacks. Patch name: 345c9a50ab07018f1b4439776bad78a0d40778ec. To fix this issue, it is recommended to deploy a patch.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "opencc"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.2.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.1.9"
    }
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-15536"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/BYVoid/OpenCC/issues/997"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/BYVoid/OpenCC/pull/1005"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/BYVoid/OpenCC/commit/345c9a50ab07018f1b4439776bad78a0d40778ec"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/BYVoid/OpenCC"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/oneafter/1222/blob/main/repro"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?ctiid.341708"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?id.341708"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?submit.733347"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-119", "CWE-787" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-06T22:32:12Z",
    "nvd_published_at" : "2026-01-18T09:15:46Z"
  }
}