Malicious PDF — malware analysis report

Static analysis result for SHA-256 18fd5a376a44631b…

MALICIOUS

PDF

43.0 KB
MD5: 4345a8cae9655ffad952aa8de8c75eb7 SHA-1: 5fec8974be6018cd952961cd5bc97cf03cb165be SHA-256: 18fd5a376a44631b0ad5581ab62b61ec96a32afbcaf41b46b9cb651bef1d0727
176 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The file is a PDF document that triggers a critical ClamAV detection for Pdf.Exploit.Agent-36836. It also contains embedded scripts and files, indicating an attempt to exploit vulnerabilities and deliver a secondary payload. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • ClamAV: Pdf.Exploit.Agent-36836 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36836
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • Embedded script payload in PDF stream low PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/1.0/
    • http://www.xfa.org/schema/xfa-template/2.5/
    • http://ns.adobe.com/xtd/
    • http://www.xfa.org/schema/xfa-data/1.0/
    • http://ns.adobe.com/xfdf/
    • http://www.xfa.org/schema/xfa-form/2.8/

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
04462f810d6eacdacecc9d0a5f3f81bebc722af4415e04da19b520338f642b51
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xD7 67 bytes
embedded_file_obj0009.bin
685ec00ba8d1e3a207e91ad1ae9b8c5e3cbc4f5473feab31f711c3ce0e99d74b
pdf-embedded-file PDF EmbeddedFile object 9 at offset 0x162 681 bytes
embedded_file_obj0010.bin
e1ab66598406464785df1b7c3e4218452dce39c816aca3e1a181e312cbe8a05c
pdf-embedded-file PDF EmbeddedFile object 10 at offset 0x456 93 bytes
embedded_file_obj0011.bin
e06eeb309c5e7be9f24e3334854f2e9e06a1fec455a2de9e19dc02212aacd41a
pdf-embedded-file PDF EmbeddedFile object 11 at offset 0x4FE 418 bytes
embedded_file_obj0012.bin
6dfc2cfc739bf5cd5514e048143c782a1af7b4c86ed10bd88203471efa9b3fe7
pdf-embedded-file PDF EmbeddedFile object 12 at offset 0x6EB 389 bytes
embedded_file_obj0014.bin
f8952c0c69992be9a3092a0606fb9bb8cc9e38ec398f84ce2a7836c2465f0a9a
pdf-embedded-file PDF EmbeddedFile object 14 at offset 0x8BD 40936 bytes
Detection
ClamAV: Pdf.Exploit.Agent-36836
Obfuscation or payload: unlikely
embedded_file_obj0015.bin
51d6d76eddb1746e412f89f4d1c1b0d620c60fb4a5641c018e93871be63968a9
pdf-embedded-file PDF EmbeddedFile object 15 at offset 0xA8EF 147 bytes