Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1dc0319181f6d07…

MALICIOUS

PDF

83.5 KB Created: 2021-08-17 20:25:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 5c0f9d82ba9cbf7c5a518fd8181c90e0 SHA-1: 74226c99414b3bd8f3fc811143daaf9a74ba4969 SHA-256: a1dc0319181f6d0712472c178b303503f31633f1051eb504e6e9da3a24825064
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting an attempt to obscure the final malicious destination. The ML classifier strongly indicated maliciousness, supporting the conclusion that this PDF is designed to lead users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc734cdd59---23615575489.pdf In PDF document text
    • https://altonika.pro/files/fck/file/fujetadavozub.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/cvq6b6tt3p5c9f5ijd4v295s49/3617319096.pdfIn PDF document text
    • http://candientu24h.vn/webroot/img/files/99116302558.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/54235199207.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/7247064701.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/jofopa.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16095e456005e7---27910629027.pdfIn PDF document text
    • https://childconcern.in/trila/userfiles/file/50035359047.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/30940411779.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/30cd6c263b36f85210ee4de9e21bf260/tojefelaxeterujajorubugen.pdfIn PDF document text
    • https://satybharat.com/ci/userfiles/files/tiwikipavujisezon.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/24e0cb290dab2e0a96d424909bb445e4/14752494040.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/lajuvojexow.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4242250d3a---numijojapitekonotofapir.pdfIn PDF document text
    • https://www.barefoothoa.com/webroot/js/ckfinder/userfiles/files/wiwanajuxurugalo.pdfIn PDF document text
    • https://faprosid.com/file/22881138160.pdfIn PDF document text
    • http://masonlegacy.org/clients/61515/File/gagegedorotukafa.pdfIn PDF document text
    • http://johnmichaelharrisonlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/62195208243.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160808771f0363---39543886982.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/11063654968.pdfIn PDF document text
    • http://longbienco.com/js/ckfinder/userfiles/files/vixawesepatovotipug.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc1c95d7af---fukopibetedopori.pdfIn PDF document text
    • http://vtaky.sk/media/file/77762927506.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607c166aebeaa---30493612875.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b2b52e86a9d---pojamurasefiwoxujadu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=libro+de+matem%C3%A1ticas+cuarto+grado+de+primaria+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c974.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC974 11188 bytes
SHA-256: 67cb57c1b1de2b75bf61a27e471e561bd73787d5f1192ed712adce6d308511a6
font_01_sfnt_off0000e2e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000faf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF6 17416 bytes
SHA-256: 2bbb9fcf0d85c6270fc64ed29d5dd0a01c66d9e5cea5718610e61925633d7599
font_03_sfnt_off0001273c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1273C 16100 bytes
SHA-256: 505f1f16fb057e2a34e7666bb0a43a50f2e0b7bc0033e59b70183295ac12d2e9