How severe is CVE-2021-43298?

CVE-2021-43298 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-2021-43298 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-2021-43298?

CVE-2021-43298 affects Embedthis Goahead. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43298?

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-2021-43298 published?

CVE-2021-43298 was published on 2022-01-25 and last updated on 2026-06-17.

CVE-2021-43298

CVE-2021-43298 is a critical-severity vulnerability in Embedthis Goahead 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-307.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 5.0
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Embedthis Goahead
Published: 2022-01-25
Last modified: 2026-06-17

Description

The code that performs password matching when using 'Basic' HTTP authentication does not use a constant-time memcmp and has no rate-limiting. This means that an unauthenticated network attacker can brute-force the HTTP basic password, byte-by-byte, by recording the webserver's response time until the unauthorized (401) response.

Frequently asked questions

What is CVE-2021-43298?: The code that performs password matching when using 'Basic' HTTP authentication does not use a constant-time memcmp and has no rate-limiting. This means that an unauthenticated network attacker can brute-force the HTTP basic password, byte-by-byte, by recording the webserver's response time until the unauthorized (401) response.
How severe is CVE-2021-43298?: CVE-2021-43298 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-2021-43298 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-2021-43298?: CVE-2021-43298 affects Embedthis Goahead. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43298?: 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-2021-43298 published?: CVE-2021-43298 was published on 2022-01-25 and last updated on 2026-06-17.

References

https://github.com/embedthis/goahead/issues/304

Affected products (1)

cpe:2.3:a:embedthis:goahead:*:*:*:*:*:*:*:*

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