Malicious PDF — malware analysis report

Static analysis result for SHA-256 c61a739088558471…

MALICIOUS

PDF

80.2 KB Created: 2021-04-25 16:40:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1fdd7d619b1b6af08dea0f551b508df3 SHA-1: cf05c94f438223852c976a6c6db110da98b305cb SHA-256: c61a739088558471a5f4b095f2cc919e777ae59053cf959095dc131a1e819463
126 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution intent. It contains numerous embedded URLs, with several pointing to suspicious domains, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, mentions "true story of the three little pigs book", likely a lure to entice users to click on the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://nipisod.ru/strik?utm_term=true+story+of+the+three+little+pigs+book PDF link annotation
    • https://cdn.sqhk.co/risejesob/hjNtajz/dikesekogutazozujeferof.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387408/normal_6054b5bfc4c8a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376125/normal_602fb2717a6b5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404290/normal_606e39d4d1e0e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402014/normal_606599b45517f.pdfIn PDF document text
    • http://jotafitosixa.getenjoyment.net/mathematical_statistics_notes.pdfIn PDF document text
    • http://reduslim-italia.website/modernism_vs._traditionalism_art_in_paris_1888-89u6puc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4498994/normal_5ffa2d722013e.pdfIn PDF document text
    • http://ashotik.space/449384591333wviu.pdfIn PDF document text
    • https://cdn.sqhk.co/wamitavixitu/I78jbNT/bauer_bodoni_std_font.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425501/normal_5fdb598fcbcaf.pdfIn PDF document text
    • https://cdn.sqhk.co/kupuruvew/jby0Vib/messages_not_working_on_mac_mojave.pdfIn PDF document text
    • https://cdn.sqhk.co/vasibejovej/f0XSwhj/the_buzzer_radio.pdfIn PDF document text
    • https://cdn.sqhk.co/povuguzuloga/EialibA/crime_city_action_rpg_mod.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477638/normal_60565f348d5ae.pdfIn PDF document text
    • http://bidizujimon.getenjoyment.net/parigemesele.pdfIn PDF document text
    • http://lnstagram-office.com/washington_dc_covid_19_testinge5k0x.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4461202/normal_5ff34b500a325.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415304/normal_60437cd37a508.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/vigevot/leviathan_raid_guide_2019.pdfIn PDF document text
    • https://s3.amazonaws.com/pegozegi/73817551209.pdfIn PDF document text
    • https://s3.amazonaws.com/sesafefanulokam/why_is_iskcon_against_advaita_vedanta.pdfIn PDF document text
    • http://vifidumefitur.atwebpages.com/vesamajewoxukopesi.pdfIn PDF document text
    • https://s3.amazonaws.com/lorifawuvawot/heart_failure_preserved_ejection_fraction_treatment_guidelines.pdfIn PDF document text
    • https://s3.amazonaws.com/tazibabebamep/craftsman_2550_pressure_washer_parts.pdfIn PDF document text
    • http://xevijojikutep.onlinewebshop.net/74421961520.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f9a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A9 5208 bytes
SHA-256: 98e80800ee71f7492d8e74d9946d9dd30f68f2ec0638ec2ba4a1cb73c61f71f2
font_01_sfnt_off00010b68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B68 10864 bytes
SHA-256: e941d770e8d9649c0a68683be19a1cb45f830e2539a2ecd53bf165401a58b23d