CVE-2016-2518

The MATCH_ASSOC function in NTP before version 4.2.8p9 and 4.3.x before 4.3.92 allows remote attackers to cause an out-of-bounds reference via an addpeer request with a large hmode value.

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Name	Vendor	Start Version	End Version
Ntp	Ntp	*	4.2.8 (excluding)
Ntp	Ntp	4.3.0 (including)	4.3.92 (excluding)
Ntp	Ntp	4.2.8 (including)	4.2.8 (including)
Ntp	Ntp	4.2.8-p1 (including)	4.2.8-p1 (including)
Ntp	Ntp	4.2.8-p1-beta1 (including)	4.2.8-p1-beta1 (including)
Ntp	Ntp	4.2.8-p1-beta2 (including)	4.2.8-p1-beta2 (including)
Ntp	Ntp	4.2.8-p1-beta3 (including)	4.2.8-p1-beta3 (including)
Ntp	Ntp	4.2.8-p1-beta4 (including)	4.2.8-p1-beta4 (including)
Ntp	Ntp	4.2.8-p1-beta5 (including)	4.2.8-p1-beta5 (including)
Ntp	Ntp	4.2.8-p1-rc1 (including)	4.2.8-p1-rc1 (including)
Ntp	Ntp	4.2.8-p1-rc2 (including)	4.2.8-p1-rc2 (including)
Ntp	Ntp	4.2.8-p2 (including)	4.2.8-p2 (including)
Ntp	Ntp	4.2.8-p2-rc1 (including)	4.2.8-p2-rc1 (including)
Ntp	Ntp	4.2.8-p2-rc2 (including)	4.2.8-p2-rc2 (including)
Ntp	Ntp	4.2.8-p2-rc3 (including)	4.2.8-p2-rc3 (including)
Ntp	Ntp	4.2.8-p3 (including)	4.2.8-p3 (including)
Ntp	Ntp	4.2.8-p3-rc1 (including)	4.2.8-p3-rc1 (including)
Ntp	Ntp	4.2.8-p3-rc2 (including)	4.2.8-p3-rc2 (including)
Ntp	Ntp	4.2.8-p3-rc3 (including)	4.2.8-p3-rc3 (including)
Ntp	Ntp	4.2.8-p4 (including)	4.2.8-p4 (including)
Ntp	Ntp	4.2.8-p5 (including)	4.2.8-p5 (including)
Ntp	Ntp	4.2.8-p6 (including)	4.2.8-p6 (including)
Ntp	Ntp	4.2.8-p7 (including)	4.2.8-p7 (including)
Ntp	Ntp	4.2.8-p8 (including)	4.2.8-p8 (including)
Red Hat Enterprise Linux 6	RedHat	ntp-0:4.2.6p5-10.el6.1	*
Red Hat Enterprise Linux 6.7 Extended Update Support	RedHat	ntp-0:4.2.6p5-5.el6_7.5	*
Red Hat Enterprise Linux 7	RedHat	ntp-0:4.2.6p5-22.el7_2.2	*
Ntp	Ubuntu	precise	*
Ntp	Ubuntu	trusty	*
Ntp	Ubuntu	upstream	*
Ntp	Ubuntu	vivid/stable-phone-overlay	*
Ntp	Ubuntu	wily	*
Ntp	Ubuntu	xenial	*

Potential Mitigations

Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

https://cwe.mitre.org/data/definitions/540.html

NVD	https://nvd.nist.gov/vuln/detail/CVE-2016-2518
CWE	https://cwe.mitre.org/data/definitions/125.html

Out-of-bounds Read

Weakness

Affected Software

Potential Mitigations

References

CVE-2016-2518

Out-of-bounds Read

Weakness

Affected Software

Potential Mitigations

Related Attack Patterns

References