Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa35d33ca2ef6d76…

MALICIOUS

PDF

90.2 KB Created: 2020-12-24 20:02:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7e4068d63a1b5c9cd29aedc12de85da4 SHA-1: 741f8422342652d2203edb9df83729748f72322b SHA-256: aa35d33ca2ef6d7675bebe3353470a95ca338eca621d4299232d71e825d4b20f
156 Risk Score

Malware Insights

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

This PDF file contains a large number of external links, many of which are disguised as academic resources or answers, indicating a link farm or SEO spam campaign. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, but the PDF structure itself is used to host and distribute these malicious URLs.

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://trafficel.ru/strik?utm_term=cbse+class+9+science+chapter+2+answers
    • https://nitetezelimon.weebly.com/uploads/1/3/1/4/131438651/6150779.pdf
    • https://sesuwulot.weebly.com/uploads/1/3/1/4/131438847/20758.pdf
    • https://cdn.sqhk.co/wetotuluxe/XrITHij/enyo_pharma_ipo.pdf
    • https://cdn.sqhk.co/faresawuf/ejbhitf/chocolate_mousse_recipe_no_eggs_cocoa_powder.pdf
    • https://xoropugu.weebly.com/uploads/1/3/4/7/134707238/1562688.pdf
    • https://cdn.sqhk.co/reserujaj/hcificM/fallout_76_wastelanders_crafting_legendary_weapons.pdf
    • https://cdn.sqhk.co/duzemata/jbiaeTD/bad_piggies_online_2019_games.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/530d7640-9876-46b2-821a-a61579ef3d3f/lee_furniture_outlet.pdf
    • https://uploads.strikinglycdn.com/files/63a0cb90-0fe2-4d19-9cca-caac8f3fc00e/fexotaxojiroweketejuma.pdf
    • https://s3.amazonaws.com/badodemebo/ac_dc_power_supply_circuit_without_transformer.pdf
    • https://uploads.strikinglycdn.com/files/d0e58677-3698-4ec6-8881-9740bae396c8/12872705595.pdf
    • https://uploads.strikinglycdn.com/files/24e63fb5-9ba4-4c12-9192-11477a90c1c1/the_bastard_of_istanbul.pdf
    • https://uploads.strikinglycdn.com/files/1c02c28f-8260-4047-8118-d9509f803e60/zetupodisakewamajiwujovo.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_off000124d5.bin
aff40cd1d02dda415fd21937014b62e80327298b9321e1865a5129b1b64a5e65
pdf-font-stream PDF embedded font (sfnt) at offset 0x124D5 5448 bytes
font_01_sfnt_off0001375c.bin
f09f62645a11ab68fcc399d516dab5e844a587e9c410823ac810eb271c3c16cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x1375C 10668 bytes