Which products and versions are affected by CVE-2017-17850?

Affected: Asterisk (Digium); Certified Asterisk (Digium) versions 13.1.0, 13.1.0-rc1, 13.1.0-rc2, 13.8-cert1. The full list is in the CVE brief.

Is CVE-2017-17850 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2017-17850 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2017-17850?

No public exploit code is known.

Is there a fix for CVE-2017-17850?

Fixed versions are available, including Asterisk 1:13.18.5~dfsg-1, Asterisk 13.18.4.

How urgently should CVE-2017-17850 be patched?

Brandefense priority: patch immediately, because it is very likely to be exploited soon.

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Vulnerability Intelligence

CVE-2017-17850

High

A select set of SIP messages create a dialog in Asterisk.

Published Dec 27, 2017 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2017-17850, UBUNTU-CVE-2017-17850

Key Facts

Patch immediately

CVE-2017-17850 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Asterisk (Digium), Certified Asterisk (Digium).
It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
EPSS estimates a 75% probability of exploitation in the next 30 days.
Fixed versions are available, including Asterisk 1:13.18.5~dfsg-1, Asterisk 13.18.4.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

CVSS v3.1

7.5

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS (30-day exploit likelihood)

75%

Higher than 99.5% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

None known

Get the full CVE-2017-17850 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

An issue was discovered in Asterisk 13.18.4 and older, 14.7.4 and older, 15.1.4 and older, and 13.18-cert1 and older. A select set of SIP messages create a dialog in Asterisk. Those SIP messages must contain a contact header. For those messages, if the header was not present and the PJSIP channel driver was used, Asterisk would crash. The severity of this vulnerability is somewhat mitigated if authentication is enabled. If authentication is enabled, a user would have to first be authorized before reaching the crash point.

Affected Products

12 affected entries in total

Product	Affected versions	Fixed in
AsteriskDigium	See advisory	13.18.4
Certified AsteriskDigium	13.1.0, 13.1.0-rc1, 13.1.0-rc2, 13.8-cert1	n/a

Patched Releases

Asterisk

1:13.18.5~dfsg-1, 13.18.4

Timeline

Publicly disclosed
Dec 27, 2017
Last updated
Aug 4, 2026

Weakness Type

CWE-20 Improper Input Validation

References

2 more references in the full CVE brief

FAQ

Common Questions.

An issue was discovered in Asterisk 13.18.4 and older, 14.7.4 and older, 15.1.4 and older, and 13.18-cert1 and older.
Affected: Asterisk (Digium); Certified Asterisk (Digium) versions 13.1.0, 13.1.0-rc1, 13.1.0-rc2, 13.8-cert1. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Asterisk 1:13.18.5~dfsg-1, Asterisk 13.18.4.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

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