How severe is CVE-2020-5233?

CVE-2020-5233 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity high, and availability low.

Is CVE-2020-5233 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5233?

CVE-2020-5233 affects Oauth2 Proxy Project Oauth2 Proxy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-5233?

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

When was CVE-2020-5233 published?

CVE-2020-5233 was published on 2020-01-30 and last updated on 2026-06-17.

CVE-2020-5233

CVE-2020-5233 is a medium-severity vulnerability in Oauth2 Proxy Project Oauth2 Proxy 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-601.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 5.8
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Oauth2 Proxy Project Oauth2 Proxy
Published: 2020-01-30
Last modified: 2026-06-17

Description

OAuth2 Proxy before 5.0 has an open redirect vulnerability. Authentication tokens could be silently harvested by an attacker. This has been patched in version 5.0.

Frequently asked questions

What is CVE-2020-5233?: OAuth2 Proxy before 5.0 has an open redirect vulnerability. Authentication tokens could be silently harvested by an attacker. This has been patched in version 5.0.
How severe is CVE-2020-5233?: CVE-2020-5233 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity high, and availability low.
Is CVE-2020-5233 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5233?: CVE-2020-5233 affects Oauth2 Proxy Project Oauth2 Proxy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-5233?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-5233 published?: CVE-2020-5233 was published on 2020-01-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:oauth2_proxy_project:oauth2_proxy:*:*:*:*:*:*:*:*

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