CVE-2026-87910: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-rj44-3777-mh5x
Share
CWE-22
Published
Advisory Summary

CVE-2026-87910 is a MODERATE security vulnerability vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-87910 at a Glance

CVE Identifier CVE-2026-87910
GHSA Identifier GHSA-rj44-3777-mh5x
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-87910

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

Verify Direct and Transitive Dependencies

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

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-87910, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

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

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'), where the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. In Software, 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

When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.

References

NVD — CVE-2026-87910 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-87910
Software Source Repository REPOSITORY
https://github.com/python/cpython/issues/157265
Software Source Repository REPOSITORY
https://github.com/python/cpython/pull/157266
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/2eb0c2f1dc71847731b6ab30aebefd058d482a7f
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/3105a3498aaf681ce128cf5baf83c2e5574267c5
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/764fd0af8d9e19d3684a58d2e58bf770f0605036
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/9c17bace90f88dfba6d0e2fe23c8e7ae35f83955
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/a4919937a4e1e69a0d178909c6f20557eca5d1d0
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/c1f106d240c4ffcb3608ed0a20e8aba6c865f6d3
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b
Security Fix Commit FIX COMMIT
https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2
Software Security Information SECURITY
https://mail.python.org/archives/list/security-announce@python.org/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ
Software Security Information SECURITY
http://www.openwall.com/lists/oss-security/2026/09/11/8

Frequently Asked Questions

What is CVE-2026-87910?
CVE-2026-87910 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-87910?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-87910?
CVE-2026-87910 is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.).
How can I check Maven dependencies for CVE-2026-87910?
Run the dependency tree command: 'mvn dependency:tree'. 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-rj44-3777-mh5x",
  "modified" : "2026-10-02T03:31:09Z",
  "published" : "2026-09-11T18:31:27Z",
  "aliases" : [ "CVE-2026-87910" ],
  "details" : "When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-87910"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/issues/157265"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/pull/157266"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/2eb0c2f1dc71847731b6ab30aebefd058d482a7f"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/3105a3498aaf681ce128cf5baf83c2e5574267c5"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/764fd0af8d9e19d3684a58d2e58bf770f0605036"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/9c17bace90f88dfba6d0e2fe23c8e7ae35f83955"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/a4919937a4e1e69a0d178909c6f20557eca5d1d0"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/c1f106d240c4ffcb3608ed0a20e8aba6c865f6d3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2"
  }, {
    "type" : "WEB",
    "url" : "https://mail.python.org/archives/list/security-announce@python.org/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2026/09/11/8"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T18:16:59Z"
  }
}