How severe is CVE-2021-31799?

CVE-2021-31799 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-31799 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31799?

CVE-2021-31799 primarily affects Ruby-lang Rdoc. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31799?

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-2021-31799 published?

CVE-2021-31799 was published on 2021-07-30 and last updated on 2026-06-17.

CVE-2021-31799

CVE-2021-31799 is a high-severity vulnerability in Ruby-lang Rdoc with a CVSS 3.x base score of 7.0. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.0)
CVSS v2: 4.4
EPSS exploit prediction: 1% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Ruby-lang Rdoc
Published: 2021-07-30
Last modified: 2026-06-17

Description

In RDoc 3.11 through 6.x before 6.3.1, as distributed with Ruby through 3.0.1, it is possible to execute arbitrary code via | and tags in a filename.

Frequently asked questions

What is CVE-2021-31799?: In RDoc 3.11 through 6.x before 6.3.1, as distributed with Ruby through 3.0.1, it is possible to execute arbitrary code via | and tags in a filename.
How severe is CVE-2021-31799?: CVE-2021-31799 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-31799 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31799?: CVE-2021-31799 primarily affects Ruby-lang Rdoc. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31799?: 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-2021-31799 published?: CVE-2021-31799 was published on 2021-07-30 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:a:ruby-lang:rdoc:*:*:*:*:*:ruby:*:*
cpe:2.3:a:oracle:jd_edwards_enterpriseone_tools:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

18.228.228.159 (ipv4-addr)
51.17.154.141 (ipv4-addr)
13.206.73.237 (ipv4-addr)