Malicious PDF — malware analysis report

Static analysis result for SHA-256 44576cc061f1741c…

MALICIOUS

PDF

83.7 KB Created: 2021-03-29 17:28:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 2c096333656d0cd89b585b84b3b64cb4 SHA-1: f6fdc6626f11ab84a235aba30f397a7cebabbd62 SHA-256: 44576cc061f1741c7c86737a1f7373414df185b5abb21088838a7e0dd14e8d46
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains and hosted on services like sqhk.co, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards malicious content designed to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • 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 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.
  • 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://jacksth.ru/strik?utm_term=how+to+write+a+good+objective+statement+for+a+resume PDF link annotation
    • https://cdn.sqhk.co/gosukutusu/Nf3SieU/sadofabig.pdfIn PDF document text
    • https://cdn.sqhk.co/godezixibufo/jfjatgc/make_your_own_sheet_music_book.pdfIn PDF document text
    • https://wunogalabapa.weebly.com/uploads/1/3/4/6/134603674/0e4a331ee8870b2.pdfIn PDF document text
    • https://cdn.sqhk.co/napoxanu/rYheibo/10161314516.pdfIn PDF document text
    • https://cdn.sqhk.co/retagigimusa/cKjdYun/game_f1_2016_android_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/vorebilifi/2icZgg2/uae_undersea_cable_cut.pdfIn PDF document text
    • http://degakak.sportsontheweb.net/the_backyard_homestead_planner.pdfIn PDF document text
    • http://tosefabebiribow.scienceontheweb.net/nivavivifujeravudaf.pdfIn PDF document text
    • http://rozogididibusar.sportsontheweb.net/berger_reloading_data_270_wsm.pdfIn PDF document text
    • https://cdn.sqhk.co/gujowaxexag/hPc6aUb/50356272235.pdfIn PDF document text
    • https://cdn.sqhk.co/wajerewuwer/IMdjbib/38264506952.pdfIn PDF document text
    • https://cdn.sqhk.co/kujaruwajovi/dhmMJAp/gamevil_monster_warlord_forums.pdfIn PDF document text
    • https://cdn.sqhk.co/zaliroded/gct8jg8/apple_music_for_artists_label_contact.pdfIn PDF document text
    • https://cdn.sqhk.co/foxinukepo/ieX5qZg/heart_rate_variability_athletic_performance.pdfIn PDF document text
    • https://cdn.sqhk.co/gixezovof/7djeHSr/nipoxazabaruzun.pdfIn PDF document text
    • http://bijowuxupolapi.sportsontheweb.net/cantaloupe_island_tabs.pdfIn PDF document text
    • http://jurojegame.getenjoyment.net/63131308263.pdfIn PDF document text
    • https://cdn.sqhk.co/tipefima/gje3icx/92126250604.pdfIn PDF document text
    • https://bixunirejo.weebly.com/uploads/1/3/5/3/135329058/xatena.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/kifutizijebuj/broadcom_bluetooth_software_windows_7.pdfIn PDF document text
    • https://s3.amazonaws.com/posufij/97212040818.pdfIn PDF document text
    • https://s3.amazonaws.com/widiku/losing_my_mind_over_you_meaning.pdfIn PDF document text
    • https://s3.amazonaws.com/lomogas/73220787461.pdfIn PDF document text
    • https://s3.amazonaws.com/fadupazageraf/which_is_the_best_app_for_learning_english_free.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA40 5520 bytes
SHA-256: c1dbcaa9cc72df41e8f4ae8e7b32fe0762e17dff995459e726b5a828ce983167
font_01_sfnt_off00010d05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D05 11092 bytes
SHA-256: 49b55aa6667d10ece5546313290bda45949f925c7f422446b78156a3c71e34b8
font_02_sfnt_off000132f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F5 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f