critical
CVE-2021-23017
nginx resolver off-by-one heap overwrite (RCE)
- Severity
- critical
- Affected product
- nginx
- Affected versions
- nginx ≥ 0.6.18, < 1.21.0
- Fixed in
- nginx 1.21.0
- Added to NewScan
- 2026-06-29
- Detected by
- NewScan — free, self-hosted
How NewScan reports it
COMPONENT VERSION RANGE
NewScan fingerprints nginx from its response and reports this CVE when the detected version falls inside the affected range below.
References
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