Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8d23e337b4de7ac…

MALICIOUS

PDF

77.7 KB Created: 2021-09-02 06:25:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 16c69e0e15c8cfd219a790d830809c06 SHA-1: 650e2c30e77078146ef2095634e71e3cc689d608 SHA-256: b8d23e337b4de7ac9c1b481137465e14c033aa085878ca166820b28965b85395
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to compromised WordPress upload storage and disposable hosting. These links likely serve as lures to phishing sites or malware downloaders.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a9f353c62---22404597960.pdf In PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/40011594c50b529d6d85e3183647b6a7/legojikotufenijogakurez.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/bijegaretididomobuk.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/n5v1lb1ja6u9vfjcoo7rj09po3/67786779883.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/17461292440.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/83089120614.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b3df506f77d---41002671387.pdfIn PDF document text
    • http://mallenmediations.com/mallenmediations/images/userfiles/file/71777568254.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/784b77da63ab4839e962d9fc703f9fb6/sajojapewomajaxutafosovar.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/57d2ef878c456fd4fc1f054794cb6d00/galimu.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fd60c856492---xijutaleluluvexuvipetonon.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/14583505576.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/rodisugi.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/54d370b77bc1b5ab5afac69966e8eca9/38235625185.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/84780362377.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/xuxikobup.pdfIn PDF document text
    • https://congthuonghotel.vn/app/webroot/files/images/pages/files/vunijogevogebifekarosetux.pdfIn PDF document text
    • http://dichvubaove.online/upload/files/tatejo.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/b8cd14246afa85d9d73ae9614fb0b3c5/99182001524.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16113e253ee7d2---nutazezajedogojojopa.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/2132169669.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/xuzefumekumogo.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/de29682777cfdeffe3a2e3d175ac9105/detavufegujevetemido.pdfIn PDF document text
    • http://kozszemle.hu/uploads/files/sunarakezenuwuta.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=over+the+selvage+custom+fabricPDF 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_off0000c8d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8D4 17740 bytes
SHA-256: 5b0ef3f3213cff451b76682ce82efa36cb26f3746eb365a26e245a8ca1314a70
font_01_sfnt_off0000f6c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C5 11008 bytes
SHA-256: 829f16efac6df79af1490e602e4efa9687e7fcd75e3b5a119e53fc95f9c657c9
font_02_sfnt_off0001107e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1107E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1