How severe is CVE-2021-31330?

CVE-2021-31330 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-31330 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31330?

CVE-2021-31330 primarily affects Reviewboard Review Board. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31330?

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

When was CVE-2021-31330 published?

CVE-2021-31330 was published on 2022-05-11 and last updated on 2026-06-17.

CVE-2021-31330

CVE-2021-31330 is a medium-severity vulnerability in Reviewboard Review Board with a CVSS 3.x base score of 5.4. 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 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Reviewboard Review Board
Published: 2022-05-11
Last modified: 2026-06-17

Description

A Cross-Site Scripting (XSS) vulnerability exists within Review Board versions 3.0.20 and 4.0 RC1 and earlier. An authenticated attacker may inject malicious Javascript code when using Markdown editing within the application which remains persistent.

Frequently asked questions

What is CVE-2021-31330?: A Cross-Site Scripting (XSS) vulnerability exists within Review Board versions 3.0.20 and 4.0 RC1 and earlier. An authenticated attacker may inject malicious Javascript code when using Markdown editing within the application which remains persistent.
How severe is CVE-2021-31330?: CVE-2021-31330 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-31330 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31330?: CVE-2021-31330 primarily affects Reviewboard Review Board. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31330?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-31330 published?: CVE-2021-31330 was published on 2022-05-11 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:reviewboard:review_board:3.0.20:*:*:*:*:*:*:*
cpe:2.3:a:reviewboard:review_board:4.0:beta1:*:*:*:*:*:*
cpe:2.3:a:reviewboard:review_board:4.0:beta2:*:*:*:*:*:*
cpe:2.3:a:reviewboard:review_board:4.0:rc1:*:*:*:*:*:*

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