CVE-2021-27279

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

0.96% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 59.0% of scored records. A rank, not a probability.

NVD base score

5.4 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-02-22 19:04Z5 YR AGO

Last updated

2024-08-03 20:48Z2 YR AGO

Reserved

2021-02-16

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Base

Data version

5.1

Document digest

5e683b22e4bde9209d8994da493907179eb6fa60ed076972a44cdacd264d43ef

• mybb.comhttps://mybb.com/versions/1.8.25/x_refsource_MISC
• github.comhttps://github.com/mybb/mybb/security/advisories/GHSA-6483-hcpp-p75wx_refsource_CONFIRM
• github.comhttps://github.com/mybb/mybb/commit/cb781b49116bf5c4d8deca3e17498122b701677ax_refsource_CONFIRM