CVE-2021-36884: Authenticated Persistent Cross-Site Scripting (XSS) vulnerability discovered in WordPress Backup Migration plugin <= 1.1.5 versions.

medium Affects backup-backup (WordPress plugin). Feed 2026.10.29.4, updated 2026-10-29; published 2021-11-19; advisory modified 2026-06-17.

Authenticated Persistent Cross-Site Scripting (XSS) vulnerability discovered in WordPress Backup Migration plugin <= 1.1.5 versions.

Package: backup-backup (WordPress plugin) WordPress
Affected versions: <=1.1.5
Fixed in: no fix recorded
Severity: medium CVSS 4.8
Exploitation: not on CISA KEV · EPSS 1% (47.1th percentile)
Published: 2021-11-19
Source: nvd

References

CWE-79

NVD record backup-backup (WordPress plugin) advisories

Am I affected?

Find out in one command. phpwarden checks your WordPress install against this advisory and 20,000+ others, ranked by real-world exploitation (CISA KEV + EPSS). Free, offline, open data.

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# then
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Or keep it checked automatically with the GitHub Action or a nightly cron; see WordPress docs.

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