Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aac98625aeb45a8…

MALICIOUS

PDF

41.7 KB Created: 2020-08-12 00:09:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f431af9b3d55b45ddbdef5462aaa4cf8 SHA-1: bb704de8bfb9be0002b1081940e3b5026362fdcf SHA-256: 4aac98625aeb45a89fce27ef17eab106d08ee93b26b5e6ac87f22a16dae002f2
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, including one pointing to a known malicious redirector at 'https://ttraff.cc/pify?keyword=walking+bass+guitar+tab+pdf'. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' confirms this. Additionally, the 'PDF_SEO_LINK_FARM' heuristic indicates a large number of links, many hosted on cdn.shopify.com, suggesting an attempt to manipulate search engine results or distribute malicious content. The ML classifier also strongly flagged this PDF as malicious.

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=walking+bass+guitar+tab+pdf
    • http://files.citygirlsensibility.com/uploads/1/3/1/4/131407274/zasararulera.pdf
    • http://files.raveneyeimagery.com/uploads/1/3/0/7/130740591/suluropekawosixi.pdf
    • http://files.grassyforkelementary.com/uploads/1/3/1/8/131871467/eec994f72a42f8b.pdf
    • https://cdn.shopify.com/s/files/1/0435/4244/6231/files/rujivubidemo.pdf
    • https://cdn.shopify.com/s/files/1/0431/6971/0242/files/siduloruxu.pdf
    • https://cdn.shopify.com/s/files/1/0428/3600/0931/files/samozelijazovijubuseleno.pdf
    • https://cdn.shopify.com/s/files/1/0429/2182/0326/files/95162984659.pdf
    • https://cdn.shopify.com/s/files/1/0434/2949/4940/files/22219882472.pdf
    • https://cdn.shopify.com/s/files/1/0433/7713/1683/files/14855992687.pdf
    • https://cdn.shopify.com/s/files/1/0427/4143/2487/files/zeluzeromosekojiwitig.pdf
    • https://cdn.shopify.com/s/files/1/0435/0168/2843/files/attached_book_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0431/4755/9067/files/gozuzisate.pdf
    • https://cdn.shopify.com/s/files/1/0430/8949/4177/files/international_accounting_standards_14.pdf
    • https://cdn.shopify.com/s/files/1/0437/0278/0072/files/rheem_thermostat_manual.pdf
    • https://cdn.shopify.com/s/files/1/0430/9493/3665/files/sewimo.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_off00006481.bin
5b58fa36eca73161137facd968c5bb4bfbc8a72c16d9f2b639829734069f45ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x6481 5428 bytes
font_01_sfnt_off0000770b.bin
751b96a365919e0521ee2e061f768104d5189c83b979c89e6e398ae7dbe5928e
pdf-font-stream PDF embedded font (sfnt) at offset 0x770B 10212 bytes