How severe is CVE-2016-5431?

CVE-2016-5431 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-5431 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-5431?

CVE-2016-5431 affects Php Jose Project Php Jose. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-5431?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2016-5431 published?

CVE-2016-5431 was published on 2019-08-07 and last updated on 2026-06-17.

CVE-2016-5431

CVE-2016-5431 is a high-severity vulnerability in Php Jose Project Php Jose with a CVSS 3.x base score of 7.5. 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-327.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-327
Affected product: Php Jose Project Php Jose
Published: 2019-08-07
Last modified: 2026-06-17

Description

The PHP JOSE Library by Gree Inc. before version 2.2.1 is vulnerable to key confusion/algorithm substitution in the JWS component resulting in bypassing the signature verification via crafted tokens.

Frequently asked questions

What is CVE-2016-5431?: The PHP JOSE Library by Gree Inc. before version 2.2.1 is vulnerable to key confusion/algorithm substitution in the JWS component resulting in bypassing the signature verification via crafted tokens.
How severe is CVE-2016-5431?: CVE-2016-5431 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-5431 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-5431?: CVE-2016-5431 affects Php Jose Project Php Jose. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-5431?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2016-5431 published?: CVE-2016-5431 was published on 2019-08-07 and last updated on 2026-06-17.

References

https://github.com/nov/jose-php/commit/1cce55e27adf0274193eb1cd74b927a398a3df4b

Affected products (1)

cpe:2.3:a:php_jose_project:php_jose:*:*:*:*:*:*:*:*

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