Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7266f8eaa4151e6…

MALICIOUS

PDF

36.7 KB Created: 2020-08-09 19:53:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e7cc0f13556df09ebf5cd332b0188b64 SHA-1: 8018e55e1d07285a41aaebb5a5a6e6a4d3ee55b9 SHA-256: a7266f8eaa4151e692bbf538db1ca161f744efb9ea1561090029ae7090c8fc32
154 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, pointing to a URL that is part of a link farm designed to manipulate search engine results. The document body, though heavily obfuscated, contains text related to graphing functions and the malicious URL, suggesting a lure to trick users into clicking the link. 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.com/pify?keyword=graphing+absolute+value+functions+worksheet+pdf+answers
    • http://files.barneyspumps.com/uploads/1/3/2/3/132302940/8842740.pdf
    • http://files.canaanchristianministries.co.uk/uploads/1/3/2/8/132814030/juxenosopanube.pdf
    • http://files.wviolin.com/uploads/1/3/1/8/131871852/xerizumaruri.pdf
    • http://files.fauxmesticgoddess.com/uploads/1/3/1/8/131856381/gevaxil.pdf
    • https://cdn.shopify.com/s/files/1/0431/5312/9640/files/nijusomomanesemirube.pdf
    • https://cdn.shopify.com/s/files/1/0429/5216/3482/files/49145640892.pdf
    • https://cdn.shopify.com/s/files/1/0435/8638/8123/files/0._as_a_fraction.pdf
    • https://cdn.shopify.com/s/files/1/0429/3967/8886/files/46330133135.pdf
    • https://cdn.shopify.com/s/files/1/0434/2205/6600/files/tapetitamaluguvozadod.pdf
    • https://cdn.shopify.com/s/files/1/0432/3534/4539/files/wemigubub.pdf
    • https://cdn.shopify.com/s/files/1/0434/8575/7606/files/wozofibumejajaval.pdf
    • https://cdn.shopify.com/s/files/1/0429/8702/8641/files/73698029704.pdf
    • https://cdn.shopify.com/s/files/1/0431/5516/1252/files/viwajokavizujasoj.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/71409998288.pdf
    • https://cdn.shopify.com/s/files/1/0430/2536/7193/files/24903161362.pdf
    • https://cdn.shopify.com/s/files/1/0437/5353/7685/files/cch_tch_trang_online.pdf
    • https://cdn.shopify.com/s/files/1/0446/5816/3865/files/edit_text_acrobat_9.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_off00005078.bin
3f0c0ea66dc0d0def0b8453c60d64505badd35d844ff191eec8d4b919f0106fc
pdf-font-stream PDF embedded font (sfnt) at offset 0x5078 5804 bytes
font_01_sfnt_off00006447.bin
b7268a783859e6b9be2acb18e1ba61a147c517a1326796c55317bd644d75d559
pdf-font-stream PDF embedded font (sfnt) at offset 0x6447 9668 bytes