Malicious PDF — malware analysis report

Static analysis result for SHA-256 99912de1b852e9fe…

MALICIOUS

PDF

84.5 KB Created: 2021-09-07 07:43:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 959ff15ed302f8379336313aa338bd46 SHA-1: dddce9f398419fc6dafabd41dd9f30d9686f54ec SHA-256: 99912de1b852e9fe9889efd6edc0618702da9ebff5e64a97f1a7a9cb886dc019
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on compromised websites, indicating a link farm or distribution mechanism. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.aifimm.it/admin/inc/ckfinder/userfiles/files/devunimitezetesep.pdf In PDF document text
    • https://newtech-utm.pl/userfiles/file/vepupadigaragaz.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/lerifowofujisa.pdfIn PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/83343924920.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160750100a15f1---91769285082.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/5a4464737653a3fb181dcd4d398637c4/74759850089.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2bdb577b0---45596399244.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/50be72c8c1396e31731b3dff2f5c65d8/xaren.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd39b04624---97712610593.pdfIn PDF document text
    • http://likebarcode.com/image/files/20210715_071428.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/77441829295.pdfIn PDF document text
    • http://msiutilities.biz/documents/fopol.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160e64d467c7a4---gareruxomitikutemibozup.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/bq7omjfug8g5qeptedud3srbg3/vuxawagewisowisosi.pdfIn PDF document text
    • http://naplesredeals.com/userfiles/files/mamak.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/88588922538.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/20d2de82d1f995ed6438490d76c53ad6/xajoxugiboxupojofaboketu.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202104/file/14029198588.pdfIn PDF document text
    • http://www.pilatesyoga.hr/files/files/kovovemapebukedo.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/1594af64476052f1d9f70df739780572/93140784072.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/gozatuvemigifegasar.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9b0e4f33b---leforo.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/1mpadu2o7kph3a7k6fofjsvvtp/dawabibajibujebid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=frise+chronologique+de+l%27histoire+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_off0000dfbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBC 10996 bytes
SHA-256: cb6d95567173ce7f733b4c55e46e60856d41aff8fcf58e4a201f2627f097a510
font_01_sfnt_off0000f8ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8AB 20248 bytes
SHA-256: eab1a1622243b41f1cae3f0f14512d6696ed5392036594c08a57e928f65fe7e6
font_02_sfnt_off00012be7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1