Malicious PDF — malware analysis report

Static analysis result for SHA-256 8141dffa86815b3a…

MALICIOUS

PDF

80.1 KB Created: 2021-08-13 11:22:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: a0cd0687997d72f1d68121b164b2a6ad SHA-1: 45e742251c492bbffd877d25a62e7395ef7f61a7 SHA-256: 8141dffa86815b3ad2485599e70100d87eda3d2d48c14c1bbe95c42956b6f073
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS upload directories, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malicious redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160859e0a3d9ed---vowavaxemomigewaja.pdf In PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/2a95ef7e4b8f879de7bfbe5762a0a9de/3321405975.pdfIn PDF document text
    • http://gapoom.com/upload/fckeditor/file/47022382850.pdfIn PDF document text
    • http://springgalleryng.com/Images_upload/files/11208693992.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/c3076cb9515623ad8803c679f8ed1981/11484616209.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d712f382eb---webovej.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/89648930471.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160df92e4373f2---sepuvijosurasepitator.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/momigunukumur.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/68399513322.pdfIn PDF document text
    • http://willbramephotography.com/gegutelolel.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/xigizifol.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/8cf37c73d6078f11ee9c0da646f784f4/sizenu.pdfIn PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/aa12221e60f83a90bd027b3b99181edd/68921255423.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16079744c77d87---51744028181.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/17642146895.pdfIn PDF document text
    • https://indirimlipin.com/calisma2/files/uploads/8343966866.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/2202bc886718e346774e34461495c4b9/48170273421.pdfIn PDF document text
    • http://wellfoto.cz/pictures/files/47331347632.pdfIn PDF document text
    • https://groupunsur3.com/contents//files/33371889387.pdfIn PDF document text
    • http://perseverance.cyou/updatefiles/file/11254588484.pdfIn PDF document text
    • http://xingyeknitting.com/userfiles/files/28019223481.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16072f9abbb50e---14677953693.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8cec096de---7038759330.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf96c510d60---36753929836.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=aqa+level+2+further+maths+pdfPDF 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_off0000d4aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ecc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC1 10860 bytes
SHA-256: a0c01a155432760faadfa6bfbeb98e2be8a65d865f344ffef831862e901776b1
font_02_sfnt_off000105ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BA 17216 bytes
SHA-256: ae5aa4131ab5e575c93be44c5ecbb338a417c2874b5fce1f438dbcd968937f28