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CVE-2021-23017 Public exploit EPSS 53.5%

A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from…

Summary

The flaw is an off-by-one error in the nginx resolver component, which handles DNS responses. An attacker who can forge UDP packets appearing to come from the DNS server can trigger a one-byte memory overwrite, crashing a worker process and potentially enabling other impact.

Official description · CVE.org

A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from the DNS server to cause 1-byte memory overwrite, resulting in worker process crash or potential other impact.

Breakdown
28.7 / 100
Exploited
Not confirmed
Reports
1
Tactics
0/15

Public exploit code (PoC-in-GitHub) appeared 7 months after disclosure. No confirmed exploitation is recorded.

  1. Disclosedday 0
  2. Public exploit codePoC-in-GitHub+7 mo

techniques

No techniques linked

No ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.

What security researchers reported

Named in 1 threat report
1 reportTrustwave

Reports are matched by finding the exact id CVE-2021-23017 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.

References

14 links, grouped by NVD tag
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