CVE-2023-49786 Asterisk susceptible to Denial of Service via DTLS Hello packets during call initiation

2023-12-1419:47:46

CWE-703

GitHub_M

www.cve.org

asterisk

dtls

dos

7.5 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

7.8 High

AI Score

Confidence

High

0.005 Low

EPSS

Percentile

76.7%

JSON

Asterisk is an open source private branch exchange and telephony toolkit. In Asterisk prior to versions 18.20.1, 20.5.1, and 21.0.1; as well as certified-asterisk prior to 18.9-cert6; Asterisk is susceptible to a DoS due to a race condition in the hello handshake phase of the DTLS protocol when handling DTLS-SRTP for media setup. This attack can be done continuously, thus denying new DTLS-SRTP encrypted calls during the attack. Abuse of this vulnerability may lead to a massive Denial of Service on vulnerable Asterisk servers for calls that rely on DTLS-SRTP. Commit d7d7764cb07c8a1872804321302ef93bf62cba05 contains a fix, which is part of versions 18.20.1, 20.5.1, 21.0.1, amd 18.9-cert6.

CNA Affected

[
  {
    "vendor": "asterisk",
    "product": "asterisk",
    "versions": [
      {
        "version": "< 18.20.1",
        "status": "affected"
      },
      {
        "version": ">= 19.0.0, < 20.5.1",
        "status": "affected"
      },
      {
        "version": "= 21.0.0",
        "status": "affected"
      },
      {
        "version": "< 18.9-cert6",
        "status": "affected"
      }
    ]
  }
]