Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cb37cba9076bc8b…

MALICIOUS

PDF

68.0 KB Created: 2020-11-24 13:42:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b06680820a1d89f1e876c0728c771ae4 SHA-1: 12c8a2aecac35423e37398d2da03962587225e02 SHA-256: 4cb37cba9076bc8bbe6c7afbae6f8502282892ab0be71a6ed01b77390354e309
214 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://traffmen.ru/strik?utm_term=sam+jones+flash+gordon+instagram'. Additionally, it exhibits characteristics of a PDF link farm, with numerous links to external PDFs, one of which is 'https://s3.amazonaws.com/busutafitufe/muzozutebupafadejedone.pdf'. The ML classifier and ClamAV also flagged this file as malicious, indicating a phishing or trojan-like behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://traffmen.ru/strik?utm_term=sam+jones+flash+gordon+instagram
    • https://cdn-cms.f-static.net/uploads/4426073/normal_5fa45eec77139.pdf
    • https://tujulita.weebly.com/uploads/1/3/4/6/134687611/61b3504cac6af4.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/busutafitufe/muzozutebupafadejedone.pdf
    • https://s3.amazonaws.com/nuruvapozixix/composite_science_and_technology_template.pdf
    • https://s3.amazonaws.com/lebejos/38152881477.pdf
    • https://s3.amazonaws.com/luresimosip/mokedekapikulufot.pdf
    • https://s3.amazonaws.com/tuxutedi/mavunufozosafojadonu.pdf
    • https://s3.amazonaws.com/putelekireza/voludotebixaruvodoziwekel.pdf
    • https://s3.amazonaws.com/bokexizometun/folug.pdf
    • https://s3.amazonaws.com/batoragubukepo/muslim_baby_girl_names_with_meaning_in_tamil.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_off0000cb4d.bin
1fbda52a1ceef95a435dd61617bd4b63598bcc129ce9fcb537a800ff9361b2c9
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB4D 5500 bytes
font_01_sfnt_off0000ddd5.bin
45e42670f8b345b7f79d2bd619cc8b1323a9bb97e8500a40ece0bc535f5a0e9d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD5 11168 bytes