What’s Vulnerable › Vulnerabilities

CVE-2019-20786

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.0% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-04-19 · updated 2026-06-17
• Weakness: CWE-287

Description

handleIncomingPacket in conn.go in Pion DTLS before 1.5.2 lacks a check for application data with epoch 0, which allows remote attackers to inject arbitrary unencrypted data after handshake completion.

Affected products

• pion dtls: before 1.5.2 — fixed in 1.5.2

How to fix

Upgrade to a fixed version: pion dtls 1.5.2. Check the vendor advisory for mitigations.

References

• https://github.com/pion/dtls/commit/fd73a5df2ff0e1fb6ae6a51e2777d7a16cc4f4e0
• https://github.com/pion/dtls/compare/v1.5.1...v1.5.2
• https://www.usenix.org/conference/usenixsecurity20/presentation/fiterau-brostean
• https://www.usenix.org/system/files/sec20fall_fiterau-brostean_prepub.pdf
• https://github.com/pion/dtls/commit/fd73a5df2ff0e1fb6ae6a51e2777d7a16cc4f4e0
• https://github.com/pion/dtls/compare/v1.5.1...v1.5.2
• https://www.usenix.org/conference/usenixsecurity20/presentation/fiterau-brostean
• https://www.usenix.org/system/files/sec20fall_fiterau-brostean_prepub.pdf

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