How severe is CVE-2021-3680?

CVE-2021-3680 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-3680 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3680?

CVE-2021-3680 affects Showdoc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3680?

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

When was CVE-2021-3680 published?

CVE-2021-3680 was published on 2021-08-04 and last updated on 2026-06-17.

CVE-2021-3680

CVE-2021-3680 is a medium-severity vulnerability in Showdoc with a CVSS 3.x base score of 4.9. 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-347.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 4.0
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Showdoc
Published: 2021-08-04
Last modified: 2026-06-17

Description

showdoc is vulnerable to Missing Cryptographic Step

Frequently asked questions

What is CVE-2021-3680?: showdoc is vulnerable to Missing Cryptographic Step
How severe is CVE-2021-3680?: CVE-2021-3680 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-3680 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3680?: CVE-2021-3680 affects Showdoc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3680?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3680 published?: CVE-2021-3680 was published on 2021-08-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:showdoc:showdoc:*:*:*:*:*:*:*:*

More vulnerabilities in Showdoc

CVE-2022-0362 — Critical (CVSS 9.8): SQL Injection in Packagist showdoc/showdoc prior to 2.10.3.
CVE-2021-41745 — Critical (CVSS 9.8): ShowDoc 2.8.3 ihas a file upload vulnerability, where attackers can use the vulnerability to obtain server permissions.
CVE-2021-36440 — Critical (CVSS 9.8): Unrestricted File Upload in ShowDoc v2.9.5 allows remote attackers to execute arbitrary code via the 'file_url'…
CVE-2021-4168 — High (CVSS 8.8): showdoc is vulnerable to Cross-Site Request Forgery (CSRF)
CVE-2021-4017 — High (CVSS 8.8): showdoc is vulnerable to Cross-Site Request Forgery (CSRF)
CVE-2022-0409 — High (CVSS 7.8): Unrestricted Upload of File with Dangerous Type in Packagist showdoc/showdoc prior to 2.10.2.

All CVEs affecting Showdoc →

Other CWE-347 (Improper Verification of Cryptographic Signature) vulnerabilities

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CVE-2022-24884 — Critical (CVSS 10.0): ecdsautils is a tiny collection of programs used for ECDSA (keygen, sign, verify). `ecdsa_verify_[prepare_]legacy()`…
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Browse all CWE-347 (Improper Verification of Cryptographic Signature) vulnerabilities →