Malicious PDF — malware analysis report

Static analysis result for SHA-256 688c1df48b9e0dee…

MALICIOUS

PDF

84.6 KB Created: 2021-03-20 21:44:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: afa69931c956aa65ab9b154b08ea70cb SHA-1: 3b67506dbf3cf2dffa75a2ffc0f7a8c2b3d80bfc SHA-256: 688c1df48b9e0deecda10fcb8aad547915bef5300591b9ad51d707d700479ceb
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on disposable domains, indicative of a link farm or phishing campaign. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://druttle.ru/award?keyword=cds+full+syllabus+pdf PDF link annotation
    • http://polikarmonolit.ru/que_es_una_empresa_comercialgmxxn.pdfIn PDF document text
    • http://digtalcaliper09.xyz/wojuludatubejebuvefgnmhk.pdfIn PDF document text
    • https://cdn.sqhk.co/nobukomorur/EgdQide/flip_folder_for_trombone.pdfIn PDF document text
    • https://cdn.sqhk.co/vamapoludi/akhiCT5/girl_ludo_king_game_guardian_script.pdfIn PDF document text
    • http://bupetud.xyz/my_son_the_fanatic_movie_summaryeo2q2.pdfIn PDF document text
    • https://cdn.sqhk.co/pivugisaxap/Md8Vjig/sinoletiluvotilawanenuti.pdfIn PDF document text
    • http://filmera.ru/writer_who_stuck_her_head_in_the_oven48cjc.pdfIn PDF document text
    • http://flowerport.market/mlb_schedule_2021_cardinalsfrg55.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cf782450-ee2f-4124-9f59-22da1bde113b.filesusr.com/ugd/c4f63d_37ba2e28124244a5ac4d8d2efdd8b37b.pdf?index=trueIn PDF document text
    • https://0e8f88b9-656e-4b05-9cd8-8bd477f85547.filesusr.com/ugd/95b9ea_7d9b2ee132fa484087af00d69e801e3a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ceb98601-ef4c-40d9-beec-48d1eda9501a/58253958161.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30a90826-87a3-4f3d-a9e7-e5430726bd47/2012_jeep_grand_cherokee_overland_tire_size.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54caa5c9-0793-49f7-ab48-8f36f40ab8c8/how_many_volumes_does_berserk_anime_cover.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b8ca5d6-19fe-4468-be39-d974b8063d8c/61464733631.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6b6bc26-800d-4079-985c-7ac31803f511/78788156674.pdfIn PDF document text
    • https://8b7199fc-a029-4910-8138-caee300d1cbd.filesusr.com/ugd/da8f68_6aa6c9d89d3747f1b5aeda3c01b4279c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/263ea3d9-3256-476f-a7ec-4fbcb4495d9e/what_are_the_end_results_of_cellular_respiration.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1e0f557f-c88e-4c1f-b1e7-46cf3ee943a4/33388531550.pdfIn PDF document text
    • https://6f4861c6-cdf0-4a5f-ba2d-f9c5e5bfbee6.filesusr.com/ugd/77941b_6210410477774b7fbe9b0970a30e4593.pdf?index=trueIn PDF document text
    • https://c3e810f9-371e-40b9-9a0b-4695a496ec77.filesusr.com/ugd/2c7c49_a70024d58c0a4693b3448cd45b5d7bc6.pdf?index=trueIn PDF document text
    • https://0bdb67af-4c57-4a6e-9706-714cc80719f5.filesusr.com/ugd/fc840b_108980861ec84b908877fcac5bc46945.pdf?index=trueIn PDF document text
    • https://36622f5a-5a1b-41a5-aa98-965156e47ac2.filesusr.com/ugd/804ff6_1bfdf5a53fbd4bf3aa03d847c780497c.pdf?index=trueIn PDF document text
    • https://0e01c86c-6ad9-43de-bc04-b8819f410213.filesusr.com/ugd/73c254_4a8a7b2ddce34f6bb8f388ccb1e0325c.pdf?index=trueIn 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_off00010e54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E54 5084 bytes
SHA-256: d22ecc435be6bd01014d06281b0207f110cfa464a0b1c617118cff34d73f4931
font_01_sfnt_off00011fb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB3 10920 bytes
SHA-256: 99ca49c1d6672b3045b2cf64f306cd793a1ec132f4835c10f5e2ebe08e8a0c17