Malicious PDF — malware analysis report

Static analysis result for SHA-256 928b860471cc9fcd…

MALICIOUS

PDF

86.7 KB Created: 2021-04-07 23:47:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 917a21d5360fbad5df9f40494d0d46b5 SHA-1: caa7049a23e27841a0e7ea8d36136a16aa44fb31 SHA-256: 928b860471cc9fcd98b7750e55281b99805b8e34f6cd8266b5417bb04c6b7e93
186 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 disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware delivery mechanism, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pelibifir.ru/strik?utm_term=the+white+queen+and+the+white+princess+timeline PDF link annotation
    • https://cdn.sqhk.co/wazikunal/dwjdwRx/there_s_a_butcher_around_no_pokies.pdfIn PDF document text
    • https://cdn.sqhk.co/gesuwetok/dgdxjjv/blacksmith_leveling_guide_classic_wow.pdfIn PDF document text
    • https://cdn.sqhk.co/pufuxogife/jaggiky/sector_14_market_gurgaon_location.pdfIn PDF document text
    • https://cdn.sqhk.co/jotenitix/cghZiid/color_hockey_hack_mod_apk.pdfIn PDF document text
    • http://jetolad.iblogger.org/33788382837.pdfIn PDF document text
    • https://cdn.sqhk.co/moradivovep/gdUjdTB/lutif.pdfIn PDF document text
    • https://cdn.sqhk.co/wotirixa/jaiahes/picsay_pro_photo_editing_app.pdfIn PDF document text
    • https://cdn.sqhk.co/mugolino/3yMhc8j/sasowupenuzadowu.pdfIn PDF document text
    • https://cdn.sqhk.co/ninivaxibab/jb4RhjT/modern_simple_cv_template_word_free.pdfIn PDF document text
    • https://cdn.sqhk.co/putuziboki/rGwgcjc/21717741209.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1cd0d4d5-11d4-440c-a307-81f73801f601.filesusr.com/ugd/f0e51d_46ec87afcdac4d0ea093f16a7fa5aafe.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8bbfd083-d646-469a-9b13-14deed669b2e/towasi.pdfIn PDF document text
    • https://d4f4546a-a836-4b3d-8651-c56b89608eca.filesusr.com/ugd/3e9e83_c81adac1457d4d8c85893ba84eb8e99f.pdf?index=trueIn PDF document text
    • http://mukoluduxoge.rf.gd/oropharyngeal_airway_size_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09016fc6-7418-41bf-891d-123bc8632680/which_is_the_coldest_place_in_the_world_and_its_temperature.pdfIn PDF document text
    • https://4b002d3c-a55f-42ce-816c-238f848e88a9.filesusr.com/ugd/3398cc_cc9117ed4aa94981a30dc64524af33cc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/91ca05b0-f4a1-4812-8c10-53a0cb49e90c/how_do_i_change_the_battery_in_my_dustbuster.pdfIn PDF document text
    • https://a1f0096d-76f5-425c-b826-5ccbd312c1bc.filesusr.com/ugd/8f8c07_7550a9b51e894f76aa2a9dde03b9ca4e.pdf?index=trueIn PDF document text
    • https://43a2ba88-5de9-465b-b95f-6a4d82f2d06e.filesusr.com/ugd/dcbeda_9e31e7ecd89f415687057c5596e3a9b9.pdf?index=trueIn PDF document text
    • https://de2a8dfc-dc8d-4d62-be3b-f97abdd17bf6.filesusr.com/ugd/c722c2_25a3dfab1cd24c99bd480bfa188ad7ae.pdf?index=trueIn PDF document text
    • https://8f6f9f04-f977-4239-955d-f6aecf2dd879.filesusr.com/ugd/81cd61_3bf06a6f973a4b4281b39dd21ce65e74.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d8fe5501-4427-4574-bea9-a344eed3df04/pezederotisiwur.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C5 5480 bytes
SHA-256: e0f77dde89418d0e008a79d70102ac604e5d3d264f655d722f7a602326e2841b
font_01_sfnt_off00010b4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4E 11416 bytes
SHA-256: 182687a7c673fe3a864b07d928d6ec9b85f7c1dd370687c6c4d6f04ce86b4a43
font_02_sfnt_off00013176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13176 18036 bytes
SHA-256: 3ae503c3f8fdfa102b67fe8681f6e23c556177f5ce15d1b88ffe6d0ab70d6444