How severe is CVE-2026-77387?

CVE-2026-77387 has a CVSS score of 4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-77387?

CVE-2026-77387 affects the following packages: geopy (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2026-77387?

Update geopy to 2.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-77387 is resolved across your whole dependency graph.

How do I detect CVE-2026-77387 in my PyPI dependencies?

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

How do I mitigate CVE-2026-77387 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2026-77387 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-77387 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-2026-77387?

CVE-2026-77387 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 9th 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-2026-77387?

CVE-2026-77387 is classified as CWE-1333 (CWE-1333). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-77387 published, and has it been updated?

CVE-2026-77387 was published on October 1, 2026 and was last updated on October 4, 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

MEDIUM severity

CVE-2026-77387 — geopy

MEDIUMFix: geopy/geopy@5d09fa8

CVE-2026-77387 is a medium-severity (CVSS 4) CWE-1333 vulnerability in geopy. A fix is available for geopy — see the affected versions and patch details below.

geopy: Regular Expression Denial of Service (ReDoS) in geopy.Point

Also known asGHSA-mhvh-fq92-pfmr

Published

Oct 1, 2026

Updated

Oct 4, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-77387.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs9th percentile — riskier than 9% of all scored CVEsHighest risk

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

How urgent is this, really

CVE-2026-77387 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 384,189 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐍geopy

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

geopy.Point and Point.from_string() may take excessive CPU time when parsing long, malformed coordinate strings due to inefficient regular-expression behavior. The numeric Point constructor is not affected.

Geocoders' reverse methods called with string inputs exercise the vulnerable path.

Applications are affected when they pass attacker-controlled strings to these APIs without an appropriate length limit. Repeated requests may cause denial of service.

Patches

Fixed in geopy 2.5.0 by rejecting overly long (over 256 characters) coordinate strings before parsing.

Workarounds

Limit coordinate strings to a reasonable maximum length, such as 256 characters, before passing them to geopy.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`geopy`	all versions	2.5.0`pip install --upgrade 'geopy==2.5.0'`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for geopy, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update geopy to 2.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-77387 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

### Impact `geopy.Point` and `Point.from_string()` may take excessive CPU time when parsing long, malformed coordinate strings due to inefficient regular-expression behavior. The numeric Point constructor is not affected. Geocoders' `reverse` methods called with string inputs exercise the vulnerable path. Applications are affected when they pass attacker-controlled strings to these APIs without an appropriate length limit. Repeated requests may cause denial of service. ### Patches Fixed in geopy **2.5.0** by rejecting overly long (over 256 characters) coordinate strings before parsing. #