INDICATOR-OBFUSCATION -- Snort detected a system behavior that suggests the system has been affected by malware. That behavior is known as an Indicator of Compromise (IOC). The symptoms could be a wide range of behaviors, from a suspicious file name to an unusual use of a utility. Symptoms do not guarantee an infection; your network configuration may not be affected by malware, but showing indicators as a result of a normal function. This alert specifically refers to a method of disguising code, known as obfuscation. Obfuscation methods are used to perform innocent convenience tasks (for instance, Javascript used to condense Jquery scripts, or a compiler using obfuscation to protect the full code for NDA reasons), or it could be used to hide an attack.
INDICATOR-OBFUSCATION Gzip encoded HTTP response with no Content-Length or chunked Transfer-Encoding header
This event is generated when HTTP traffic is gzip encoded without a content length or chunked transfer encoding in the header. This is used by exploit kits as an evasion technique. Impact: Detection of a non-standard protocol or event Details: Ease of Attack:
This event is generated when HTTP traffic is gzip encoded without a content length or chunked transfer encoding in the header. This is used by exploit kits as an evasion technique.
No public information
No known false positives
Cisco Talos Intelligence Group
No rule groups
None
No information provided
None
Tactic: Exfiltration
Technique: Data Compressed
For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org
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