CVE-2017-12259

What it is

A vulnerability in the implementation of Session Initiation Protocol (SIP) functionality in Cisco Small Business SPA51x Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to become unresponsive, resulting in a denial of service (DoS) condition. The vulnerability is due to the improper handling of SIP request messages by an affected device. An attacker could exploit this vulnerability by sending malformed SIP messages to an affected device. A successful exploit could allow the attacker to cause the affected device to become unresponsive, resulting in a DoS condition that persists until the device is restarted manually. This vulnerability affects Cisco Small Business SPA51x Series IP Phones that are running Cisco SPA51x Firmware Release 7.6.2SR1 or earlier. Cisco Bug IDs: CSCvc63982.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

2.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2017-10-19 08:29 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 01:02 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 2.3% in the next 30 days (EPSS).
• Severity: 7.5 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2017-10-19 08:29 UTC

Last modified

2026-06-17 01:02 UTC

Exploit probability

2.3% · EPSS, next 30 days

Weakness

CWE-119 · Buffer errors

Record status

Modified

Affected

• Cisco Small Business Ip Phone Firmware ≤ 7.6.2

Attack profile CVSS 3.0 · 7.5

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2017-12259.md and follow it. Check whether this project is affected by CVE-2017-12259. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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