Malicious PDF — malware analysis report

Static analysis result for SHA-256 d15fe31f64fd7845…

MALICIOUS

PDF

68.0 KB Created: 2020-12-24 04:17:20 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8fccc1195f18623251d4aa9aa7d93b14 SHA-1: 76b7a05c94e3104b155d9e8fd938f8e40f087755 SHA-256: d15fe31f64fd7845b064963dd740d3815a2b01c83b165d79fb12125884cf36bd
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to S3 buckets and CDNs, suggesting a link farm or SEO manipulation tactic. One prominent URL, 'https://trafffi.ru/strik?utm_term=color+pillar+satisfying+smooth+free+games', is presented as a lure for free games. ClamAV and ML heuristics confirm the malicious nature, classifying it as a phishing trojan. No scripts were extracted, but the PDF structure itself is used to host numerous external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://trafffi.ru/strik?utm_term=color+pillar+satisfying+smooth+free+games
    • https://cdn.sqhk.co/lizupasepafu/hhhcjgm/8727791155.pdf
    • https://cdn.sqhk.co/kopizikob/byYpic5/2234210978.pdf
    • https://cdn.sqhk.co/kuxefoxo/4oijGDm/zalozobewidufadojelago.pdf
    • https://fudukonuxevefez.weebly.com/uploads/1/3/4/6/134606022/tuwovibupixopi_nizapiregiweret_zoborakov.pdf
    • https://cdn.sqhk.co/bufutoje/gf3uRl8/21962068734.pdf
    • https://cdn-cms.f-static.net/uploads/4380403/normal_5f8b3f3bbb634.pdf
    • https://cdn.sqhk.co/govovazeket/yMyichc/chess_grandmaster_game_download_for_pc.pdf
    • https://sewuvemap.weebly.com/uploads/1/3/4/3/134377394/955590.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/xukirizugukugi/vowuwix.pdf
    • https://s3.amazonaws.com/varoximu/apoptosis_muerte_celular_programada.pdf
    • https://s3.amazonaws.com/loranoduzuja/andalusia_font_free.pdf
    • https://s3.amazonaws.com/tokit/house_of_fun_slots_on_facebook.pdf
    • https://s3.amazonaws.com/savifin/dslr_camera_starter_guide.pdf
    • https://s3.amazonaws.com/memul/past_simple_and_present_continuous_exercises.pdf
    • https://s3.amazonaws.com/pizexopenaxu/bevunokofitiramed.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_off0000c8eb.bin
934529ca31b6fc2553b376ad52185c4c970436d22abc19811362c81e939f2fbb
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8EB 5320 bytes
font_01_sfnt_off0000dae2.bin
d2313f39444f3529129f78075cb5cfd2903a53af9c89f6a37e47288d657a90db
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE2 11008 bytes