CVE-2017-17850

CVE-2017-17850 is a high-severity vulnerability in Digium Asterisk with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 75% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

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.

Frequently asked questions

What is CVE-2017-17850?
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.
How severe is CVE-2017-17850?
CVE-2017-17850 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2017-17850 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 75% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-17850?
CVE-2017-17850 primarily affects Digium Asterisk. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-17850?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2017-17850 published?
CVE-2017-17850 was published on 2017-12-27 and last updated on 2026-06-17.

References

Affected products (5)

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