Malicious PDF — malware analysis report

Static analysis result for SHA-256 933ffec3227ca0e5…

MALICIOUS

PDF

74.4 KB Created: 2021-09-22 11:46:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2e7af40e238f68da4a5a6cc77fba4e45 SHA-1: d2dd694ccf780639a59f2bcc558f1a142f62ead8 SHA-256: 933ffec3227ca0e587eb3d64240539a3936784683f44763d219de83dc016d5cc
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by an ML classifier as malicious and contains numerous embedded URLs. Several heuristics indicate it functions as a link farm, with some links pointing to compromised CMS upload storage. The presence of embedded URLs and the link farm structure suggest an attempt to redirect users to malicious sites, likely as part of a phishing or SEO poisoning campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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://garnet-medical.com/userfiles/files/8451906017.pdf In PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16148a841ddc10---dupefix.pdfIn PDF document text
    • http://fcgo.tw/uploadpic/files/69263535139.pdfIn PDF document text
    • http://csc-0411.com/userfiles/file/20210909081959_hiwlfk.pdfIn PDF document text
    • http://studio70.eu/userfiles/files/91665183407.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/bizebazifusoboloxokel.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/5884747764.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/jn4bsjitnsd4v1a887mf2jsjcq/40579846972.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/nudedaganixo.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/xobijado.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/xavulizinawepinawulapo.pdfIn PDF document text
    • https://zebcom.in/userfiles/file/raguwenudonovo.pdfIn PDF document text
    • https://www.bakkersvlaanderen.be/resources/plugins/ckfinder/userfiles/0/files/18491414849.pdfIn PDF document text
    • https://mayersoffice.com/userfiles/file/zilinewukibona.pdfIn PDF document text
    • http://synergyproperty.com/images/files/69758624554.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202109150615408207.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/161339fd027116---fozewesigajinusij.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/1s3lf9udnu8jvp8m4iqubtocm4/banata.pdfIn PDF document text
    • https://revive.fashion/upload/files/7886094558.pdfIn PDF document text
    • http://acutecardio.ru/sadm_files/34907213508.pdfIn PDF document text
    • https://bahispesinde.com/gnc/veri/_files/tiliwapar.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/93267377437.pdfIn PDF document text
    • https://batdongsandothanh.vn/luutru/files/90956343817.pdfIn PDF document text
    • http://sanxuatbanthinghiem.org/app/webroot/uploads/files/fumumovoribinopopezu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=android+mms+settingsPDF 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_off0000c252.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC252 10364 bytes
SHA-256: 47d482da13deef0584117a465850759ce1f4649d98ab578d61eb92e7b6980dce
font_01_sfnt_off0000d982.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD982 16648 bytes
SHA-256: 6a67fd707ca00e35b0874934a6585b8f08c77640ff176e68249a9bd66ec59c62
font_02_sfnt_off00010482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10482 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1