Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1f7771a4715f57d…

MALICIOUS

PDF

74.8 KB Created: 2021-09-01 21:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 482f675b0ef5aac4c3531315f68234f2 SHA-1: 504e166cae91cda41df04f10b898b73f00a2ccb3 SHA-256: d1f7771a4715f57d857add3a6dbbae608be7f710123935eed1e86dae06a5dd61
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised websites, suggesting it's designed to lure users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a link farm used for initial compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • 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 http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759534c7a50---44169664933.pdf In PDF document text
    • https://homestayhoian.vn/uploads/image/files/pemexetevagalik.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee3d2f38c36---jatilaketorog.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/bae524550b3a08ed4aa1d26c85054d27/sinixevidab.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/61939764160.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/1f03e068e1c03b323c2f64eb05b33606/85868095910.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/nebofa.pdfIn PDF document text
    • http://mariopresto.pl/userfiles/file/3379565158.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/83adcb185f8702a2294675cf2846cae2/kenojir.pdfIn PDF document text
    • http://fqcycpa.com/jingkelun/userfiles/files/20210806215112.pdfIn PDF document text
    • http://koslita.eu/ckfinder/userfiles/files/madolekunobesixugosewes.pdfIn PDF document text
    • http://servmed.net/userfiles/file/xonituniforobudiragusuw.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8bbcad3720---tuxudumorisori.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610895c19b029---nemivofubipedolevudir.pdfIn PDF document text
    • http://asavn.vn/uploads/userfiles/files/57530795160.pdfIn PDF document text
    • https://arerp.kr/data/file///53184846197.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607428b48a1fc---sekuduvugaxoduluvaraga.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/3561135437.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+sign+cat+in+aslPDF link annotation
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/lixutopu.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_off0000c160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC160 10248 bytes
SHA-256: a972768085ef2a4b0581960e0dbd57b604cb2b408f3bcbedb049afb7df4be28a
font_01_sfnt_off0000d88f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD88F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A1 17832 bytes
SHA-256: a5954b3d052127f57fddc4b8d389c6d55048bc2d7a87404ecf1d460a59476bd8