Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b4a6e1427628e9a…

MALICIOUS

PDF

42.0 KB Created: 2020-08-09 02:26:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c8be18981e51a9683609abc970b7e384 SHA-1: 7c20c024569e53091c51ded6b3467e1bdd45da37 SHA-256: 8b4a6e1427628e9ab1173130e9218d6368a05357eb7dd64c7bfd8d321231f307
152 Risk Score

Malware Insights

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

The PDF contains numerous links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.com/pify?keyword=aeronautical+engineering+books+free+download+pdf', suggesting a lure for users seeking free engineering books. This link likely leads to a malicious site, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. 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=aeronautical+engineering+books+free+download+pdf
    • http://files.hollytheater.com/uploads/1/3/1/4/131453251/4029980.pdf
    • http://begepe.cpasgc.com/uploads/1/3/0/7/130776485/jobijoka-wuwepak-warar.pdf
    • http://files.stylisticat.com/uploads/1/3/2/6/132680781/be29d929b92d557.pdf
    • https://cdn.shopify.com/s/files/1/0434/7294/5304/files/command_prompt_tricks_to_hack_wifi.pdf
    • https://cdn.shopify.com/s/files/1/0431/1410/2950/files/nubudozi.pdf
    • https://cdn.shopify.com/s/files/1/0427/6636/8935/files/sims_4_urban_hair_cc.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/15906675896.pdf
    • https://cdn.shopify.com/s/files/1/0432/7620/6235/files/33951097663.pdf
    • https://cdn.shopify.com/s/files/1/0430/7176/6677/files/48970806984.pdf
    • https://cdn.shopify.com/s/files/1/0434/0239/5813/files/advanced_engineering_mathematics_zill.pdf
    • https://cdn.shopify.com/s/files/1/0438/1458/4477/files/asmaul_husnah_dan_artinya.pdf
    • https://cdn.shopify.com/s/files/1/0436/7931/8166/files/cms_1500_fillable.pdf
    • https://cdn.shopify.com/s/files/1/0433/7837/6853/files/lupuvopulopileko.pdf
    • https://cdn.shopify.com/s/files/1/0429/5278/6074/files/fidiwadujezewunuv.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/
    • https://cdn.shopify.com/s/files/1/0430/7176/6677/files

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006478.bin
992468b95e758c52267ff8222a21f00be5650b4730074ba0228046ba4fe22a63
pdf-font-stream PDF embedded font (sfnt) at offset 0x6478 5608 bytes
font_01_sfnt_off000077a6.bin
aa5c75fb31f90259715309cbed1ef9d27f10e8f2368ff7ddfee2e69e41d9f937
pdf-font-stream PDF embedded font (sfnt) at offset 0x77A6 10296 bytes