Malicious PDF — malware analysis report

Static analysis result for SHA-256 8738651f5f8c39ef…

MALICIOUS

PDF

46.8 KB Created: 2020-08-07 16:14:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 487fc6f9ce87f7f0dacacaaf50803571 SHA-1: f975682f249cad01b74d6b97b1f781514199b8f3 SHA-256: 8738651f5f8c39efaad95bac120b36e5e0e51e9a8523264fd374229546c654f2
154 Risk Score

Malware Insights

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

The PDF contains numerous links, including one to a known malicious redirector at 'ttraff.com'. The document body, though heavily obfuscated, contains text suggesting a lure related to 'classroom language for teachers pdf'. The presence of many external PDF links, some benign and some unknown, indicates a link farm or SEO poisoning attempt to distribute malicious content. The ML classifier 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=classroom+language+for+teachers+pdf
    • http://files.hooves2pawsllc.com/uploads/1/3/0/7/130740130/vijin.pdf
    • http://tamekapo.nextlevelsnowboarding.com/uploads/1/3/1/3/131381428/7912177.pdf
    • http://files.shopvinocellars.com/uploads/1/3/1/4/131406592/295643.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/38743570217.pdf
    • https://cdn.shopify.com/s/files/1/0431/7016/8986/files/mefasirigi.pdf
    • https://cdn.shopify.com/s/files/1/0437/7100/3031/files/pezirupujep.pdf
    • https://cdn.shopify.com/s/files/1/0427/7737/8972/files/rivebulitizomelatona.pdf
    • https://cdn.shopify.com/s/files/1/0433/8260/3927/files/zovobiwumajawefu.pdf
    • https://cdn.shopify.com/s/files/1/0435/1492/1114/files/aliens_love_underpants_book.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/sutapazuvonovojikujabera.pdf
    • https://cdn.shopify.com/s/files/1/0431/7220/0608/files/dimadakaloladagepoj.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/70277109097.pdf
    • https://cdn.shopify.com/s/files/1/0429/5992/9503/files/18198726651.pdf
    • https://cdn.shopify.com/s/files/1/0429/5042/6787/files/aarushi_talwar_judgement.pdf
    • https://cdn.shopify.com/s/files/1/0432/3350/9534/files/prentice_hall_biology_answer_keys.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_off000077b1.bin
63b9b18174ef61221db6fa13d5a52525799293e9541e4e50ca3076e8de0d74ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x77B1 5476 bytes
font_01_sfnt_off00008a1f.bin
5c8a3b2f1668c03391ecff2a7720e17d854c25571b1dae902f49bc87425b60c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x8A1F 10464 bytes