How severe is CVE-2021-4437?

CVE-2021-4437 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-4437 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4437?

CVE-2021-4437 affects Dbartholomae Lambda-middleware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4437?

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

Does CVE-2021-4437 have an EU (EUVD) identifier?

Yes. CVE-2021-4437 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0667.

When was CVE-2021-4437 published?

CVE-2021-4437 was published on 2024-02-12 and last updated on 2026-06-17.

CVE-2021-4437

CVE-2021-4437 is a low-severity vulnerability in Dbartholomae Lambda-middleware with a CVSS 3.x base score of 3.5. 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-1333.

Key facts

Severity: Low (CVSS 3.x base score 3.5)
CVSS v2: 2.7
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0667
Weakness: CWE-1333
Affected product: Dbartholomae Lambda-middleware
Published: 2024-02-12
Last modified: 2026-06-17

Description

A vulnerability, which was classified as problematic, has been found in dbartholomae lambda-middleware frameguard up to 1.0.4. Affected by this issue is some unknown functionality of the file packages/json-deserializer/src/JsonDeserializer.ts of the component JSON Mime-Type Handler. The manipulation leads to inefficient regular expression complexity. Upgrading to version 1.1.0 is able to address this issue. The patch is identified as f689404d830cbc1edd6a1018d3334ff5f44dc6a6. It is recommended to upgrade the affected component. VDB-253406 is the identifier assigned to this vulnerability.

Frequently asked questions

What is CVE-2021-4437?: A vulnerability, which was classified as problematic, has been found in dbartholomae lambda-middleware frameguard up to 1.0.4. Affected by this issue is some unknown functionality of the file packages/json-deserializer/src/JsonDeserializer.ts of the component JSON Mime-Type Handler. The manipulation leads to inefficient regular expression complexity. Upgrading to version 1.1.0 is able to address this issue. The patch is identified as f689404d830cbc1edd6a1018d3334ff5f44dc6a6. It is recommended to upgrade the affected component. VDB-253406 is the identifier assigned to this vulnerability.
How severe is CVE-2021-4437?: CVE-2021-4437 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-4437 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4437?: CVE-2021-4437 affects Dbartholomae Lambda-middleware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4437?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-4437 have an EU (EUVD) identifier?: Yes. CVE-2021-4437 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0667.
When was CVE-2021-4437 published?: CVE-2021-4437 was published on 2024-02-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:dbartholomae:lambda-middleware:*:*:*:*:*:*:*:*

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