CVE-2021-1879

Exploitation

Exploited in the wild. Listed in the CISA Known Exploited Vulnerabilities catalog on 2021-11-03. Federal remediation due 2021-11-17.

SSVC decision

• ExploitationactiveCISA reports credible evidence of active exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

7.08% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 93.7% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Analyzed. 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

2021-04-02 18:07Z5 YR AGO

Last updated

2025-10-21 23:25Z10 MO AGO

Reserved

2020-12-08

Assigning CNA

apple

Record state

PUBLISHED

Severity

Medium (CVSS 6.1)

CNA CVSS vector

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

Weaknesses

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

Data version

5.1

Document digest

574c3212cbb3521160c191f1ed21e4aeec9669c1deb9b5f29c3f6f3465d62c59

• support.apple.comhttps://support.apple.com/en-us/HT212256x_refsource_MISC
• support.apple.comhttps://support.apple.com/en-us/HT212257x_refsource_MISC
• support.apple.comhttps://support.apple.com/en-us/HT212258x_refsource_MISC
• www.cisa.govhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1879government-resource