Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bc7ae72bb57be17…

MALICIOUS

PDF

39.5 KB Created: 2020-08-21 17:56:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0bc8cb922c415575f9a2d1f7a311fea5 SHA-1: 9f33721a47122791982a5ca8fff90e86c0363d20 SHA-256: 3bc7ae72bb57be17fda3de0215fefeee3907a7a7dae9dddc5445cee4da7b9492
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded links, many of which point to Shopify domains hosting other PDFs, suggesting a link farm for SEO manipulation. One critical heuristic identified a link to a known malicious redirector, ttraff.cc, which is used to obscure the final destination. The document body, though heavily obfuscated, contains the text 'feudal system worksheets' and the malicious URL, indicating a lure to trick users into clicking the link.

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.cc/pify?keyword=feudal+system+worksheets
    • http://files.tucsonconnect.org/uploads/1/3/0/9/130969354/e1f5c0.pdf
    • http://patom.ad-fare.com/uploads/1/3/1/4/131453060/8668237.pdf
    • http://files.upandaboutroofing.com/uploads/1/3/0/7/130776327/revodenav_getezumovazif_tilusipaxotoxu.pdf
    • https://cdn.shopify.com/s/files/1/0434/4610/8312/files/fugume.pdf
    • https://cdn.shopify.com/s/files/1/0434/5187/5481/files/nipuzexule.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/dedapefe.pdf
    • https://cdn.shopify.com/s/files/1/0432/4481/4500/files/lobisesopuzagozeniko.pdf
    • https://cdn.shopify.com/s/files/1/0430/9604/7783/files/aws_certified_solutions_architect_associate_tutorial.pdf
    • https://cdn.shopify.com/s/files/1/0432/3350/9534/files/45776170798.pdf
    • https://cdn.shopify.com/s/files/1/0448/2488/7456/files/business_management_download.pdf
    • https://cdn.shopify.com/s/files/1/0434/2205/6600/files/47568557484.pdf
    • https://cdn.shopify.com/s/files/1/0433/2974/9147/files/counting_numbers_in_french.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_off00005cb1.bin
e50b207e2308bc85c94109d4680370c0822891d36417d50dafe2d2e3d085eea8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CB1 5280 bytes
font_01_sfnt_off00006e97.bin
46a38e013f686e397d7aead0fde482751e539060435f3487ea16073d5415168d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E97 10304 bytes