Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e32d99d0ae82591…

MALICIOUS

PDF

90.5 KB Created: 2021-09-05 12:26:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a5ccbf67ad2c9a27d94b94ccc98ec541 SHA-1: 24bd6a1b9e2ceab5ee06d08c82c624840328c2e7 SHA-256: 4e32d99d0ae82591fe73630311780aa430dcbf7c4b84e0bef82da87c2f06fff2
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable domains, indicating a link farm or SEO manipulation tactic. The ML classifier also flagged this PDF as malicious with high confidence. No scripts were extracted, and the document body was unreadable, so the primary attack pattern is inferred from the URL analysis and heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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 http://gustosandvic.com/ckfinder/userfiles/files/duxajonofusajoxave.pdf In PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0bf2ad061---7914653331.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a0d4113dccd0dbd6be7ebe4e1caa92cf/fifowovixozor.pdfIn PDF document text
    • http://gocep.org/data/userfiles/files/supikitamujebilanu.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160868c51d16ba---rotopugur.pdfIn PDF document text
    • http://vo23.ru/upload/file/vibojulivonuxu.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/pitusazexu.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/53224385649.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/tul6eb3sb62tothg90dl6j7jq2/nusenipu.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8e13ebff0---kijomitut.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/jitaranufugekurew.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608074358ace1---16450385152.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed7b7aecaf---35266648929.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b7bb40959c7---75632661911.pdfIn PDF document text
    • https://cupanghitam.com/contents//files/80314185799.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/t4gsaatalm70gp04fqv30t8o29/46719170124.pdfIn PDF document text
    • http://tnslib.net/userfiles/files/42871125585.pdfIn PDF document text
    • https://almuhja.com/ckfinder/userfiles/files/kitonakudin.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/teferozomaloxewobi.pdfIn PDF document text
    • https://irish-setter-zucht.info/ckfinder/userfiles/files/18097393780.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210630065729.pdfIn PDF document text
    • http://juentai.com/userfiles/files/2176774276.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/89842871327.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/69537440522.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b97ee942a---vatepe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=oxford+discover+2+workbook+pdf+free+downloadPDF 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_off0000d21a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21A 25104 bytes
SHA-256: 907f1f747b3a971264147f616576cbd586a33c39d927339f184afce2028c91aa
font_01_sfnt_off00010f8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F8C 11144 bytes
SHA-256: d450e7f15bc943a75338514f8962080b77cc4b5af1ef2c3129f3619bdeacbe2e
font_02_sfnt_off0001299e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1299E 16652 bytes
SHA-256: 424872215efef481b1066a5281b31dd8136b4b11b6c31acc71adbe7c9779e16a
font_03_sfnt_off00014151.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14151 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1