How severe is CVE-2018-20200?

CVE-2018-20200 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-20200 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20200?

CVE-2018-20200 affects Squareup Okhttp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20200?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-20200 published?

CVE-2018-20200 was published on 2019-04-18 and last updated on 2026-06-17.

CVE-2018-20200

CVE-2018-20200 is a medium-severity vulnerability in Squareup Okhttp with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 2% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Squareup Okhttp
Published: 2019-04-18
Last modified: 2026-06-17

Description

CertificatePinner.java in OkHttp 3.x through 3.12.0 allows man-in-the-middle attackers to bypass certificate pinning by changing SSLContext and the boolean values while hooking the application. NOTE: This id is disputed because some parties don't consider this is a vulnerability. Their rationale can be found in https://github.com/square/okhttp/issues/4967

Frequently asked questions

What is CVE-2018-20200?: CertificatePinner.java in OkHttp 3.x through 3.12.0 allows man-in-the-middle attackers to bypass certificate pinning by changing SSLContext and the boolean values while hooking the application. NOTE: This id is disputed because some parties don't consider this is a vulnerability. Their rationale can be found in https://github.com/square/okhttp/issues/4967
How severe is CVE-2018-20200?: CVE-2018-20200 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-20200 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20200?: CVE-2018-20200 affects Squareup Okhttp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20200?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-20200 published?: CVE-2018-20200 was published on 2019-04-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:squareup:okhttp:*:*:*:*:*:*:*:*

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