CVE-2026-42351: Pygeoapi Path Traversal Vulnerability

HIGH
Advisory Identifier: GHSA-f6pr-83pg-ghh6
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CVSS 7.5
CWE-22
Published
Advisory Summary

CVE-2026-42351 is a HIGH (CVSS 7.5) path traversal vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting Pygeoapi libraries in the PyPI ecosystem. The issue involves path traversal in stac filesystemprovider. Remediation is available by upgrading affected packages to version 0.23.3.

CVE-2026-42351 at a Glance

CVE Identifier CVE-2026-42351
GHSA Identifier GHSA-f6pr-83pg-ghh6
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product Pygeoapi
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.5

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

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

How to Fix CVE-2026-42351

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

pygeoapi fixed: 0.23.3 
pip install pygeoapi>=0.23.3
Verify Direct and Transitive Dependencies

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

pip show pygeoapi

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-42351, inspect your installed packages using pip:

pip show pygeoapi

Analyze the terminal output to locate any version of Pygeoapi in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.23.3), your application is affected.

Note: The pip show pygeoapi command checks currently installed packages in your active Python environment.

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 Pygeoapi, 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

### Impact A raw string path concatenation vulnerability in pygeoapi's STAC FileSystemProvider plugin can allow for requests to STAC collection based collections to expose directories without authentication. The issue manifests when pygeoapi is deployed without a proxy or web front end that would normalize URLs with `..` values, along with a resource of type `stac-collection` defined in configuration. ### Patches The issue has been patched in master branch and made available as part of the 0.23.3 release. The commit/fix can be found in [bf25b8695edbdd5476eeffc102b633d1d3e45f52](https://github.com/geopython/pygeoapi/commit/bf25b8695edbdd5476eeffc102b633d1d3e45f52). ### Workarounds Users can safeguard existing applications by disabling STAC collection based resources in their pygeoapi config, until 0.23.3 can be installed and deployed.

CVE-2026-42351 Affected Pygeoapi Versions

1 component(s)
Fixed Versions:
0.23.3
Product / Package Ecosystem Affected Versions Fixed Version
pygeoapi
pypi/pygeoapi
PyPI
≥ 0.23.0
< 0.23.3
0.23.3

References

GitHub Advisory / Wiki ADVISORY
https://github.com/geopython/pygeoapi/security/advisories/GHSA-f6pr-83pg-ghh6
NVD — CVE-2026-42351 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42351
Security Fix Commit FIX COMMIT
https://github.com/geopython/pygeoapi/commit/bf25b8695edbdd5476eeffc102b633d1d3e45f52
Pygeoapi Source Repository REPOSITORY
https://github.com/geopython/pygeoapi
Pygeoapi Release RELEASE
https://github.com/geopython/pygeoapi/releases/tag/0.23.3

Frequently Asked Questions

What is CVE-2026-42351?
CVE-2026-42351 is a security vulnerability in Pygeoapi involving Path Traversal in STAC FileSystemProvider under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which Pygeoapi versions are affected?
Affected versions include releases prior to 0.23.3 across affected packages: pygeoapi.
What version fixes CVE-2026-42351?
Upgrading to 0.23.3 (or the latest patched release for your respective branch) resolves the vulnerability.
Is pygeoapi affected?
Yes, pygeoapi is affected in releases prior to 0.23.3. Upgrade your dependency to 0.23.3 or later.
What is the CVSS score of CVE-2026-42351?
CVE-2026-42351 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-42351?
CVE-2026-42351 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 PyPI dependencies for CVE-2026-42351?
Run the dependency tree command: 'pip show pygeoapi'. 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-f6pr-83pg-ghh6",
  "modified" : "2026-05-13T13:38:11Z",
  "published" : "2026-04-29T22:18:02Z",
  "aliases" : [ "CVE-2026-42351" ],
  "summary" : "pygeoapi 0.23.x: Path Traversal in STAC FileSystemProvider",
  "details" : "### Impact\nA raw string path concatenation vulnerability in pygeoapi's STAC FileSystemProvider plugin can allow for requests to STAC collection based collections to expose directories without authentication.  The issue manifests when pygeoapi is deployed without a proxy or web front end that would normalize URLs with `..` values, along with a resource of type `stac-collection` defined in configuration.\n\n### Patches\nThe issue has been patched in master branch and made available as part of the 0.23.3 release.\n\nThe commit/fix can be found in [bf25b8695edbdd5476eeffc102b633d1d3e45f52](https://github.com/geopython/pygeoapi/commit/bf25b8695edbdd5476eeffc102b633d1d3e45f52).\n### Workarounds\nUsers can safeguard existing applications by disabling STAC collection based resources in their pygeoapi config, until 0.23.3 can be installed and deployed.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "pygeoapi"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.23.0"
      }, {
        "fixed" : "0.23.3"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/geopython/pygeoapi/security/advisories/GHSA-f6pr-83pg-ghh6"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-42351"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/geopython/pygeoapi/commit/bf25b8695edbdd5476eeffc102b633d1d3e45f52"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/geopython/pygeoapi"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/geopython/pygeoapi/releases/tag/0.23.3"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-29T22:18:02Z",
    "nvd_published_at" : "2026-05-08T23:16:38Z"
  }
}