How severe is CVE-2021-33403?

CVE-2021-33403 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-2021-33403 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33403?

CVE-2021-33403 affects Blocklancertoken Project Blocklancertoken. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33403?

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-2021-33403 published?

CVE-2021-33403 was published on 2021-08-03 and last updated on 2026-06-17.

CVE-2021-33403

CVE-2021-33403 is a high-severity vulnerability in Blocklancertoken Project Blocklancertoken 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-190.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Blocklancertoken Project Blocklancertoken
Published: 2021-08-03
Last modified: 2026-06-17

Description

An integer overflow in the transfer function of a smart contract implementation for Lancer Token, an Ethereum ERC20 token, allows the owner to cause unexpected financial losses between two large accounts during a transaction.

Frequently asked questions

What is CVE-2021-33403?: An integer overflow in the transfer function of a smart contract implementation for Lancer Token, an Ethereum ERC20 token, allows the owner to cause unexpected financial losses between two large accounts during a transaction.
How severe is CVE-2021-33403?: CVE-2021-33403 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-2021-33403 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33403?: CVE-2021-33403 affects Blocklancertoken Project Blocklancertoken. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33403?: 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-2021-33403 published?: CVE-2021-33403 was published on 2021-08-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:blocklancertoken_project:blocklancertoken:-:*:*:*:*:*:*:*

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