Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1653856a28e780e…

MALICIOUS

PDF

71.7 KB Created: 2021-09-03 06:08:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2e9e36d5134c78b9c68eeee505d09009 SHA-1: e010d4574fbdd7e301e5c31123afdca41e9bc6fc SHA-256: b1653856a28e780e49b38484a48e88578800782cbffe4ff2953e8d46fac0bf9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF format and the nature of the URLs suggest it may leverage embedded JavaScript to facilitate redirection or further payload delivery.

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 http://industrialdevices.in/uploads/79089904640.pdf In PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/02f37dc02f773cdf7079f3989aaa4d14/vuwaworozijaxevalesede.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/52796519791.pdfIn PDF document text
    • https://chasehr.in/userfiles/file/refofudisotige.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/fipokosovijegiwebaroseme.pdfIn PDF document text
    • https://baoyi-chuck.com/ckfinder/userfiles/files/dibogosugulusozagabunepil.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/1563355816.pdfIn PDF document text
    • http://shahnawazonline.com/uploads/files/70692600272.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/hrv168nfdc4br3ntiqjm83jo0b/zoguxefilimesuzapakok.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/54550758105.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/87160614045.pdfIn PDF document text
    • https://amblamy.ee/upload/file/zofazudolakiwogoxumek.pdfIn PDF document text
    • https://tylbm.com/Upload/ckeditor/files/57532217517.pdfIn PDF document text
    • https://www.nevjegykiraly.hu/userfiles/files/94116234979.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/texejisawaviseb.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/4d8ecghhqttiv6udh9d0eh5tjk/50145063874.pdfIn PDF document text
    • http://araonline.hu/uploads/file/23501884896.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7ddde345df---37815800606.pdfIn PDF document text
    • http://evergladesharvesting.com/ckfinder/userfiles/files/33944512569.pdfIn PDF document text
    • http://oroblupiscine.it/userfiles/files/kesimolar.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/74543241793.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e8c493c78ed---sutufifavebopoloxadijin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=jesus+bleibet+meine+freude+pdf+violinPDF link annotation
    • 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_off0000b38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB38F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cba1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA1 17892 bytes
SHA-256: 6cc246a3e4f971b195df60f8fd28fdd21f5e83a10e4e579ef2baf7e9173bf3e9
font_02_sfnt_off0000f8b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B9 10796 bytes
SHA-256: 4b28e9296d6ced2f63f6294e03d6f8c4682bfd7c45d5fadcf00919352ec23990