How severe is CVE-2026-42351?

CVE-2026-42351 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-42351?

CVE-2026-42351 affects the following packages: pygeoapi (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2026-42351?

Update pygeoapi to 0.23.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42351 is resolved across your whole dependency graph.

How do I detect CVE-2026-42351 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pygeoapi, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-42351 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2026-42351 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-42351 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-42351?

CVE-2026-42351 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 44th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-42351?

CVE-2026-42351 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-42351 published, and has it been updated?

CVE-2026-42351 was published on May 8, 2026 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

HIGH severity

CVE-2026-42351 — pygeoapi

HIGHFix: geopython/pygeoapi@bf25b86

CVE-2026-42351 is a high-severity (CVSS 7.5) Path Traversal vulnerability in pygeoapi. A fix is available for pygeoapi — see the affected versions and patch details below.

pygeoapi: Path Traversal in STAC FileSystemProvider

Also known asGHSA-f6pr-83pg-ghh6PYSEC-2026-2985

Published

May 8, 2026

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-42351.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs44th percentile — riskier than 44% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐍pygeoapi

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

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.

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`pygeoapi`	≥ 0.23.0&&< 0.23.3	0.23.3`pip install --upgrade 'pygeoapi==0.23.3'`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pygeoapi, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pygeoapi to 0.23.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42351 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

### 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://gith