Malicious PDF — malware analysis report

Static analysis result for SHA-256 fccf1bdab00b7ee3…

MALICIOUS

PDF

43.6 KB Created: 2020-08-19 08:29:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d99c50a4f5945bdb7abda2313b3944af SHA-1: c67253b1c25cfc076ba20a4de5290101a579117a SHA-256: fccf1bdab00b7ee3cf8eb81cca4ffdeb42365d6c75b71be2e0b5c3429dbd4ffa
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing for a malicious redirector. The document body, though heavily obfuscated, contains text suggesting it is an answer key for a cloze exercise, which is likely a lure. The primary malicious URL identified is https://ttraff.ru/pify?keyword=cloze+exercise+4+adverbs+of+time+answers, which is used to redirect the user to further malicious content. The presence of a link farm heuristic further supports the malicious intent of distributing links.

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=cloze+exercise+4+adverbs+of+time+answers
    • http://wulugeg.mymotherssecrets.com/uploads/1/3/1/4/131437604/sijigixanetofigufit.pdf
    • https://cdn.shopify.com/s/files/1/0430/2353/2195/files/noxutapu.pdf
    • https://cdn.shopify.com/s/files/1/0430/3595/1257/files/96773797051.pdf
    • https://cdn.shopify.com/s/files/1/0437/9800/3874/files/popujizozimubefipido.pdf
    • https://cdn.shopify.com/s/files/1/0437/7106/8577/files/farming_books_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0430/8772/4704/files/58708711358.pdf
    • https://cdn.shopify.com/s/files/1/0430/9018/2304/files/gate_valve_images.pdf
    • https://cdn.shopify.com/s/files/1/0432/9802/9733/files/jemonaruvedisukezawusa.pdf
    • https://cdn.shopify.com/s/files/1/0433/6405/7247/files/nutidonukolikivanale.pdf
    • https://cdn.shopify.com/s/files/1/0452/9052/0738/files/nevasoligezogilesozo.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/21511039237.pdf
    • https://cdn.shopify.com/s/files/1/0437/1211/8952/files/25878467963.pdf
    • https://cdn.shopify.com/s/files/1/0448/9605/9547/files/proteger_adobe_acrobat_reader_dc.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_off00006c51.bin
8d14fbc453b02fe1756782acbe7f4fe1712c462d90fb7b555eead2517a31b414
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C51 5568 bytes
font_01_sfnt_off00007f4c.bin
91471ac8f3e8f737c324ed8b2039c296dfe0a332dcd75016c2a052864fb9158f
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F4C 10088 bytes