CAPEC-319: IP (DF) 'Don't Fragment Bit' Echoing Probe
This OS fingerprinting probe tests to determine if the remote host echoes back the IP 'DF' (Don't Fragment) bit in a response packet. An attacker sends a UDP datagram with the DF bit set to a closed port on the remote host to observe whether the 'DF' bit is set in the response packet. Some operating systems will echo the bit in the ICMP error message while others will zero out the bit in the response packet.
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Overview
CAPEC-319 (IP (DF) 'Don't Fragment Bit' Echoing Probe) is a detailed-level attack pattern catalogued by MITRE in the Common Attack Pattern Enumeration and Classification (CAPEC). It describes a recurring method attackers use to exploit software weaknesses.
Consequences
What a successful CAPEC-319 attack can achieve.
Read Data
Affects: Confidentiality
Bypass Protection Mechanism, Hide Activities
Affects: Confidentiality, Access Control, Authorization
Frequently asked questions
Common questions about CAPEC-319.
- What is CAPEC-319?
- This OS fingerprinting probe tests to determine if the remote host echoes back the IP 'DF' (Don't Fragment) bit in a response packet. An attacker sends a UDP datagram with the DF bit set to a closed port on the remote host to observe whether the 'DF' bit is set in the response packet. Some operating systems will echo the bit in the ICMP error message while others will zero out the bit in the response packet.
- What weaknesses does CAPEC-319 target?
- CAPEC-319 exploits 1 CWE weakness, including CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor).
- How severe is CAPEC-319?
- MITRE rates CAPEC-319 as Low severity with medium likelihood of attack.
References
Attack-pattern data is sourced from the MITRE CAPEC catalog (v3.9). Weakness associations link to the corresponding CWE entries on RadicalNotion.AI.
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