How severe is CVE-2021-33806?

CVE-2021-33806 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33806 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33806?

CVE-2021-33806 affects Bdew Bdlib. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33806?

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

When was CVE-2021-33806 published?

CVE-2021-33806 was published on 2021-06-03 and last updated on 2026-06-17.

CVE-2021-33806

CVE-2021-33806 is a critical-severity vulnerability in Bdew Bdlib with a CVSS 3.x base score of 9.8. 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-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Bdew Bdlib
Published: 2021-06-03
Last modified: 2026-06-17

Description

The BDew BdLib library before 1.16.1.7 for Minecraft allows remote code execution because it deserializes untrusted data in ObjectInputStream.readObject as part of its use of Java serialization.

Frequently asked questions

What is CVE-2021-33806?: The BDew BdLib library before 1.16.1.7 for Minecraft allows remote code execution because it deserializes untrusted data in ObjectInputStream.readObject as part of its use of Java serialization.
How severe is CVE-2021-33806?: CVE-2021-33806 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33806 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33806?: CVE-2021-33806 affects Bdew Bdlib. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33806?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-33806 published?: CVE-2021-33806 was published on 2021-06-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:bdew:bdlib:*:*:*:*:*:minecraft:*:*

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