Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c55528171dec473…

MALICIOUS

PDF

33.8 KB Created: 2020-08-22 04:12:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 33de8d6be1d271e577573c0cb7b6065f SHA-1: ed32e1cb84604a2ea5e44290e4556b839a2b16e4 SHA-256: 6c55528171dec473d87e367f809e9bb38709ddaf6144b73f4b664acbec4cedd9
154 Risk Score

Malware Insights

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

The PDF contains a malicious redirector link disguised as a free background image, which is a common lure for phishing attacks. The document also contains a large number of links to other PDFs, suggesting a link farm or SEO manipulation tactic. The ML classifier strongly indicated maliciousness, and the PDF structure suggests it's designed to exploit user interaction via embedded 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=blue+night+sky+background+free
    • http://files.jalanpipes.com/uploads/1/3/2/7/132740586/39285bf9b.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/9917/6612/files/acide_sulfurique_amlie_nothomb.pdf
    • https://cdn.shopify.com/s/files/1/0432/3681/9104/files/68751700332.pdf
    • https://cdn.shopify.com/s/files/1/0432/1994/3579/files/59269902757.pdf
    • https://cdn.shopify.com/s/files/1/0440/4844/9686/files/3640430697.pdf
    • https://cdn.shopify.com/s/files/1/0429/2398/3001/files/plural_nouns_exercises_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0427/8249/0791/files/house_building_design.pdf
    • https://cdn.shopify.com/s/files/1/0440/7286/1848/files/wikuwijesobapuvazumufe.pdf
    • https://cdn.shopify.com/s/files/1/0439/4817/9611/files/samefuwar.pdf
    • https://cdn.shopify.com/s/files/1/0435/4116/8283/files/animated_nursery_rhymes_free_videos.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/70913092576.pdf
    • https://cdn.shopify.com/s/files/1/0430/8166/2628/files/ketesezibibon.pdf
    • https://cdn.shopify.com/s/files/1/0437/9593/9488/files/absorcion_de_farmacos_en_el_organismo.pdf
    • https://cdn.shopify.com/s/files/1/0433/8424/2337/files/domaxijorilowedegovuzanal.pdf
    • https://cdn.shopify.com/s/files/1/0434/7949/8918/files/frequently_asked_synonyms_and_antonyms_in_ssc_cgl.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_off00004806.bin
89eed320f84dc7c8eaae6653189dfc128e7f8283c74592974570e13f5f0ea3d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x4806 5640 bytes
font_01_sfnt_off00005b31.bin
5024b4a5c79674d29181d5e440fe25d677531ea9d024fdd76fb762d1bb161ced
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B31 9196 bytes