How severe is CVE-2020-15237?

CVE-2020-15237 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-2020-15237 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-15237?

CVE-2020-15237 affects Shrinerb Shrine. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-15237?

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

When was CVE-2020-15237 published?

CVE-2020-15237 was published on 2020-10-05 and last updated on 2026-06-17.

CVE-2020-15237

CVE-2020-15237 is a medium-severity vulnerability in Shrinerb Shrine 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Shrinerb Shrine
Published: 2020-10-05
Last modified: 2026-06-17

Description

In Shrine before version 3.3.0, when using the `derivation_endpoint` plugin, it's possible for the attacker to use a timing attack to guess the signature of the derivation URL. The problem has been fixed by comparing sent and calculated signature in constant time, using `Rack::Utils.secure_compare`. Users using the `derivation_endpoint` plugin are urged to upgrade to Shrine 3.3.0 or greater. A possible workaround is provided in the linked advisory.

Frequently asked questions

What is CVE-2020-15237?: In Shrine before version 3.3.0, when using the `derivation_endpoint` plugin, it's possible for the attacker to use a timing attack to guess the signature of the derivation URL. The problem has been fixed by comparing sent and calculated signature in constant time, using `Rack::Utils.secure_compare`. Users using the `derivation_endpoint` plugin are urged to upgrade to Shrine 3.3.0 or greater. A possible workaround is provided in the linked advisory.
How severe is CVE-2020-15237?: CVE-2020-15237 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-2020-15237 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-15237?: CVE-2020-15237 affects Shrinerb Shrine. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-15237?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-15237 published?: CVE-2020-15237 was published on 2020-10-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:shrinerb:shrine:*:*:*:*:*:ruby:*:*

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