Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ff14974799dc371…

MALICIOUS

PDF

85.2 KB Created: 2021-08-03 03:56:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a44ff1b7b74252c8e37e8810e687f2d6 SHA-1: 26fed7b4becfd9b3a8dce593b50b81e6e9849f67 SHA-256: 4ff14974799dc371688ad33411a4999aae30e98ed165bd790b7d733d7cefb0c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The document body is heavily obfuscated and unreadable, suggesting it is not intended for direct user interaction but rather to facilitate the redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://rococosofa.com/files/files/11924322270.pdf In PDF document text
    • http://abaj.cz/UserFiles/File/26449315541.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/61745119145.pdfIn PDF document text
    • http://ypperfect.com/ckfinder/userfiles/files/rejorafobofim.pdfIn PDF document text
    • https://southwestlooms.com/admin/userfiles/files/9136136382.pdfIn PDF document text
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/datetuziki.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/6d5a9d4519732e51a9189609fd48fc1b/25830819953.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/36200593400.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/5ff71f6aaae3bbc77446a780de8470a6/vitam.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160ae749f5214d---sibojurugunetazudibaleja.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/kabipogovolajupekujalan.pdfIn PDF document text
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/837722becdc17df8ffa018d556dcb220/77843702567.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/bibowosozuk.pdfIn PDF document text
    • http://springhs1988.com/clients/a/a7/a70db2535ed58991dd9724faf9b165d0/File/97937354917.pdfIn PDF document text
    • http://faizleathergloves.com/userfiles/files/62061393930.pdfIn PDF document text
    • http://groupkaishan.com/d/files/66270760431.pdfIn PDF document text
    • http://deauville.ru/files/file/nusazolizanujuxalagotovo.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/nomurevuzofipofudesiforek.pdfIn PDF document text
    • https://www.xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/juvele.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607f31a898c6d---85780677920.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5613b531d---meripa.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16084a82a0966b---dariragaweluzirebemadox.pdfIn PDF document text
    • http://re-view.online/fckFiles/file/jarakem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=manufacturing+processes+for+engineering+materials+6th+edition+ebookPDF 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_off0000e3d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D5 17876 bytes
SHA-256: c853bc8d324fdb1818effea118ac31fd747b1db1e027396ea94688157b0c87e2
font_01_sfnt_off000112a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A4 11560 bytes
SHA-256: 77bae8ab11b4f574190f88a920ce33d2542136d917e7bd416aefc9c6dc9aed9f
font_02_sfnt_off00012d73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1