How severe is CVE-2021-31684?

CVE-2021-31684 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 none, and availability high.

Is CVE-2021-31684 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31684?

CVE-2021-31684 primarily affects Json-smart Project Json-smart-v1. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31684?

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-2021-31684 published?

CVE-2021-31684 was published on 2021-06-01 and last updated on 2026-06-17.

CVE-2021-31684

CVE-2021-31684 is a high-severity vulnerability in Json-smart Project Json-smart-v1 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Json-smart Project Json-smart-v1
Published: 2021-06-01
Last modified: 2026-06-17

Description

A vulnerability was discovered in the indexOf function of JSONParserByteArray in JSON Smart versions 1.3 and 2.4 which causes a denial of service (DOS) via a crafted web request.

Frequently asked questions

What is CVE-2021-31684?: A vulnerability was discovered in the indexOf function of JSONParserByteArray in JSON Smart versions 1.3 and 2.4 which causes a denial of service (DOS) via a crafted web request.
How severe is CVE-2021-31684?: CVE-2021-31684 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 none, and availability high.
Is CVE-2021-31684 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31684?: CVE-2021-31684 primarily affects Json-smart Project Json-smart-v1. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31684?: 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-2021-31684 published?: CVE-2021-31684 was published on 2021-06-01 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:json-smart_project:json-smart-v1:*:*:*:*:*:*:*:*
cpe:2.3:a:json-smart_project:json-smart-v2:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:utilities_framework:4.4.0.0.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:utilities_framework:4.4.0.2.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:utilities_framework:4.4.0.3.0:*:*:*:*:*:*:*

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