Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff3231c804717286…

MALICIOUS

PDF

41.9 KB Created: 2020-08-13 03:34:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c5437a93931a0dcff7c66b4b511b4b8c SHA-1: 58cd82d30ba108ef2dad39536714bc10411840f3 SHA-256: ff3231c8047172862a330332b5c7e884efca5c902997f5d16932261aafb70524
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a significant number of embedded links, with a critical heuristic firing for a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body contains obfuscated text and URLs, suggesting an attempt to disguise malicious content or redirect users to external sites. The primary attack pattern appears to be a link farm or SEO manipulation to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 https://ttraff.com/wb?keyword=amoxicilina%20y%20alcohol%20pdf
    • http://files.tonyottenauthor.com/uploads/1/3/2/8/132816096/zosed.pdf
    • http://files.marcelwesdorp.nl/uploads/1/3/1/3/131381540/pupuwisuru.pdf
    • http://files.voterodcasey.com/uploads/1/3/0/8/130814070/fotavadeletetov.pdf
    • http://files.clawsonspub.com/uploads/1/3/0/8/130813648/7935978.pdf
    • https://cdn.shopify.com/s/files/1/0431/4005/5208/files/ciencias_naturales_cuarto_grado.pdf
    • https://cdn.shopify.com/s/files/1/0429/2945/5263/files/dilopifopegutulesamiwo.pdf
    • https://cdn.shopify.com/s/files/1/0431/4575/6821/files/budapest_map_download.pdf
    • https://cdn.shopify.com/s/files/1/0437/4387/1127/files/list_of_punctuation_marks.pdf
    • https://cdn.shopify.com/s/files/1/0429/2100/1119/files/xozazufozidewif.pdf
    • https://cdn.shopify.com/s/files/1/0430/1353/7951/files/cub_cadet_rzt_54_manual.pdf
    • https://cdn.shopify.com/s/files/1/0429/9096/0799/files/46484298263.pdf
    • https://cdn.shopify.com/s/files/1/0452/3170/2176/files/pamewitaduvetaworoto.pdf
    • https://cdn.shopify.com/s/files/1/0429/9961/1553/files/26703198966.pdf
    • https://cdn.shopify.com/s/files/1/0437/8555/2030/files/75184553801.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000062e9.bin
de15bec00802c675ef57e2166e8ee18ae6fdd953cd12021b1b33e93bb37100eb
pdf-font-stream PDF embedded font (sfnt) at offset 0x62E9 5280 bytes
font_01_sfnt_off000074be.bin
e9cb8ea5ace9703e5b8c82e4947f982fffe63ed657dc4b99370050f539cc4e32
pdf-font-stream PDF embedded font (sfnt) at offset 0x74BE 11220 bytes