Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a81859a7b1f9d9f…

MALICIOUS

PDF

40.4 KB Created: 2020-08-21 15:30:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7f26bfb2a72cb4d5710cd5c8052d98d9 SHA-1: 6bd469eff06308c7ff39d1eca2cda3e6c4637994 SHA-256: 0a81859a7b1f9d9f36715b50a77015abfeeaad43d7fc767bb140f0dca1332830
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains a link farm and a direct link to a known malicious redirector, disguised as an answer key for the Gettysburg address. The ML classifier strongly flagged this PDF as malicious, and the presence of numerous external links suggests an attempt to distribute malicious content or engage in SEO manipulation for malicious purposes. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or redirection scheme.

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.ru/pify?keyword=gettysburg+address+worksheet+answer+key
    • http://files.horvathspecialtyauto.com/uploads/1/3/1/4/131437683/6562346.pdf
    • http://files.aplcnj.org/uploads/1/3/1/4/131453109/9267268.pdf
    • http://files.labradoodlesvermont.com/uploads/1/3/0/8/130873732/zetosoxifomebigidol.pdf
    • http://gunetoz.exorcismdetailing.com/uploads/1/3/1/4/131453433/133e7364.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/9432/7961/files/altivar_312_manual_portugues.pdf
    • https://cdn.shopify.com/s/files/1/0438/2726/5693/files/39552058840.pdf
    • https://cdn.shopify.com/s/files/1/0436/6663/6953/files/62256530586.pdf
    • https://cdn.shopify.com/s/files/1/0431/2632/5409/files/66024640731.pdf
    • https://cdn.shopify.com/s/files/1/0437/0097/7816/files/derapigasino.pdf
    • https://cdn.shopify.com/s/files/1/0436/1102/9667/files/41713223923.pdf
    • https://cdn.shopify.com/s/files/1/0428/5438/3782/files/30714417997.pdf
    • https://cdn.shopify.com/s/files/1/0433/5799/5160/files/overhead_allocation_methods.pdf
    • https://cdn.shopify.com/s/files/1/0440/2066/2422/files/52705983111.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/42479515564.pdf
    • https://cdn.shopify.com/s/files/1/0443/9313/6294/files/jellicle_cats_lyrics.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005ed9.bin
8b4683047bc7c7b843a4b49c435fe64b18535c4b29ed33e2449b6cae82202905
pdf-font-stream PDF embedded font (sfnt) at offset 0x5ED9 5484 bytes
font_01_sfnt_off0000718d.bin
1b0ea533770723fd507db35b6179e43d1883bf7136614e24d2586eb0526f3e77
pdf-font-stream PDF embedded font (sfnt) at offset 0x718D 10384 bytes