CVE-2019-20786Public exploitNetwork attack vector

Unauthenticated data injection via epoch-zero packets

Published Apr 19, 2020 · Updated Aug 5, 2024

Improper packet verification in Pion DTLS before 1.5.2 allows remote attackers to inject unencrypted application data after a handshake. handleIncomingPacket in conn.go accepts application-data records with epoch 0 and forwards their content to the decrypted-data channel. No session key is required, but a DTLS handshake must already be complete; the receiving client or server treats injected content as protected data.

CVSS severity9.8
Critical
EPSS probability3.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper packet verification in Pion DTLS before 1.5.2 allows remote attackers to inject unencrypted application data after a handshake. handleIncomingPacket in conn.go accepts application-data records with epoch 0 and forwards their content to the decrypted-data channel. No session key is required, but a DTLS handshake must already be complete; the receiving client or server treats injected content as protected data.

The record

CVE
CVE-2019-20786
Published
Apr 19, 2020
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-287, T1565.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 19, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-287Improper Authentication
T1565.002Transmitted Data Manipulation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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