How severe is CVE-2021-31239?

CVE-2021-31239 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-2021-31239 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31239?

CVE-2021-31239 affects Sqlite. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-31239?

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-2021-31239 published?

CVE-2021-31239 was published on 2023-05-09 and last updated on 2026-06-17.

CVE-2021-31239

CVE-2021-31239 is a high-severity vulnerability in Sqlite 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Sqlite
Published: 2023-05-09
Last modified: 2026-06-17

Description

An issue found in SQLite SQLite3 v.3.35.4 that allows a remote attacker to cause a denial of service via the appendvfs.c function.

Frequently asked questions

What is CVE-2021-31239?: An issue found in SQLite SQLite3 v.3.35.4 that allows a remote attacker to cause a denial of service via the appendvfs.c function.
How severe is CVE-2021-31239?: CVE-2021-31239 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-2021-31239 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31239?: CVE-2021-31239 affects Sqlite. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-31239?: 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-2021-31239 published?: CVE-2021-31239 was published on 2023-05-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sqlite:sqlite:3.35.4:*:*:*:*:*:*:*

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