Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1f3e7ec080c3ae4…

MALICIOUS

PDF

50.5 KB Created: 2020-08-23 01:32:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c931872f3c15087fe675556e78a19a86 SHA-1: 43757a664abb64355de30e18c08b62bebff6860d SHA-256: a1f3e7ec080c3ae4b7d770894244a81df598f35ecb8de110e200ca25c282bdeb
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector at 'ttraff.ru'. The document body, though heavily corrupted, contains text related to 'collecting data worksheets for kindergarten', suggesting a lure to disguise the malicious intent. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it's part of a link farm or redirection campaign.

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=collecting+data+worksheets+for+kindergarten
    • http://files.meganlewis1illustrator.com/uploads/1/3/1/6/131636855/7307786.pdf
    • http://files.margeryammon.com/uploads/1/3/1/6/131607467/47c00637c0.pdf
    • http://files.fillingthekleinbottle.com/uploads/1/3/1/6/131606343/pigisedafino_rujubu_zizuluwubob_nitap.pdf
    • https://cdn.shopify.com/s/files/1/0429/6943/2230/files/42122396353.pdf
    • https://cdn.shopify.com/s/files/1/0430/0383/8615/files/biblia_reina_valera_online.pdf
    • https://cdn.shopify.com/s/files/1/0432/1057/1940/files/nelisatomorulumogididuk.pdf
    • https://cdn.shopify.com/s/files/1/0431/6787/5221/files/pearson_texas_chemistry_textbook.pdf
    • https://cdn.shopify.com/s/files/1/0430/4253/7629/files/59280523300.pdf
    • https://cdn.shopify.com/s/files/1/0438/2985/4368/files/xotaxuviselunisofusizunu.pdf
    • https://cdn.shopify.com/s/files/1/0429/5216/3482/files/attribution_theory_psychology.pdf
    • https://cdn.shopify.com/s/files/1/0432/9144/3364/files/41510564018.pdf
    • https://cdn.shopify.com/s/files/1/0429/5147/5351/files/46136899675.pdf
    • https://cdn.shopify.com/s/files/1/0434/8113/7316/files/z_for_zachariah.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_off000088de.bin
ee1df1884c20abc427e5b4d66ba0ae2de56ad8389f1be5a82ccc5138802797fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x88DE 5344 bytes
font_01_sfnt_off00009b0f.bin
2ff645a0911d1cea66f2c507f7aee7a4baf6031c9a8c2ce03ad117a428869c8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x9B0F 9928 bytes