How severe is CVE-2021-23824?

CVE-2021-23824 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-23824 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23824?

CVE-2021-23824 affects Crowcpp Crow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23824?

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

When was CVE-2021-23824 published?

CVE-2021-23824 was published on 2022-01-13 and last updated on 2026-06-17.

CVE-2021-23824

CVE-2021-23824 is a medium-severity vulnerability in Crowcpp Crow with a CVSS 3.x base score of 6.5. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Crowcpp Crow
Published: 2022-01-13
Last modified: 2026-06-17

Description

This affects the package Crow before 0.3+4. When using attributes without quotes in the template, an attacker can manipulate the input to introduce additional attributes, potentially executing code. This may lead to a Cross-site Scripting (XSS) vulnerability, assuming an attacker can influence the value entered into the template. If the template is used to render user-generated content, this vulnerability may escalate to a persistent XSS vulnerability.

Frequently asked questions

What is CVE-2021-23824?: This affects the package Crow before 0.3+4. When using attributes without quotes in the template, an attacker can manipulate the input to introduce additional attributes, potentially executing code. This may lead to a Cross-site Scripting (XSS) vulnerability, assuming an attacker can influence the value entered into the template. If the template is used to render user-generated content, this vulnerability may escalate to a persistent XSS vulnerability.
How severe is CVE-2021-23824?: CVE-2021-23824 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-23824 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23824?: CVE-2021-23824 affects Crowcpp Crow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23824?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-23824 published?: CVE-2021-23824 was published on 2022-01-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:crowcpp:crow:*:*:*:*:*:*:*:*

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