Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc1b3573dccb4e44…

MALICIOUS

PDF

92.9 KB Created: 2021-09-04 21:44:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c4fe07a07b0b3f415ba26b91371c1c0b SHA-1: 147729c67ca744d7acf92c53b1fae7a2b8d68ed7 SHA-256: bc1b3573dccb4e44ebd81e48243a67d6f67ca3035502f496ccf72e1b778ad992
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded links are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://synerhu.ru/uplcv?utm_term=tales+of+symphonia+walkthrough+pdf PDF link annotation
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/f244a347a48ea74c0d721ea577a769c9/fobezazubi.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/81373932902.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/30808266446.pdfIn PDF document text
    • https://okazionche.com/files/bupawadewem.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/nolenesewinujopegetaz.pdfIn PDF document text
    • http://elverum-revmatiker.no/images/file/73030150322.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/20496982774.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/37151417042.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a89c89b6b---gugebaluwokixolejazu.pdfIn PDF document text
    • http://www.publicitymailing.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed0cc0fe29---86922105999.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/74518034747.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/19725649446.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d902a455fa---41228287408.pdfIn PDF document text
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16078cd86999ae---46001883581.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/feramulejojulitawemasuru.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609aacba379b0---62291582459.pdfIn PDF document text
    • http://pataibicaj.hu/userfiles/file/petalidakimowuvitavo.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/7b06d25314de6b01d84061c886210cea/71227681489.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/fef3cf09ba0786fbbda5b1cb8059a38f/2201446762.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607e67aae2acf---7749115669.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/41188054036.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094d75626a51---62930259464.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/c711575d0611c21f7e02849f5127ddd2/54676871068.pdfIn PDF document text
    • http://fhs76reunion.com/clients/0/00/009202203981f132fd14d012a57c0fe5/File/2889405448.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://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_off0001055c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1055C 17752 bytes
SHA-256: 2a523464ab386f948c6daaca236ae98ffc2ad7c4134490ab9b82a736874a07e1
font_01_sfnt_off00013327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13327 11300 bytes
SHA-256: 6746b95ba482b7557b612bdfe57e8760bf4d85c2cd395994c4a510714f4b9d34
font_02_sfnt_off00014d68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1