Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f6490035912e3d…

MALICIOUS

PDF

87.9 KB Created: 2021-09-08 20:45:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 5864b44aed46219e5629f543d59cafc7 SHA-1: 6a14352e07dbfb4758caffa35fc5f05fe6ee819b SHA-256: 83f6490035912e3d1e8b94d41308561a80970e97de25df076d7c6f59d8c0992e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to domains that appear to be disposable or compromised, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, but the structure and heuristics point to a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://coretry.ru/uplcv?utm_term=eta+movement+service+manual PDF link annotation
    • http://otoozevran.com/resimler/files/vemagosituvem.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/76112087529.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/05a2b30a1591aa34f29d23262f08b57c/neravigulilel.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/28506720542.pdfIn PDF document text
    • https://giritrademark.com/content_files/files/35150886220.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/zefeg.pdfIn PDF document text
    • https://mabuksusu2.com/contents/files/1894735413.pdfIn PDF document text
    • http://www.polni.si/Images/files/27216653562.pdfIn PDF document text
    • http://vattuxaydunghl.com/userfiles/file/13908775661.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132af9b04d84---nizabe.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/bepasafefunomadifukidij.pdfIn PDF document text
    • http://thietbibepnhahang.net/media/files/bojinefubam.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/fofasiwefafevotawagena.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161359405c32e6---wetotemalivepokowowuzigak.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/3676c914f565fcd60aad77cd47e39096/dijeralofiwebefazenu.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090209525211.pdfIn PDF document text
    • https://www.sexualaufklaerung-schule.ch/ck/ckfinder/userfiles/files/fobokoxuzexulikuke.pdfIn PDF document text
    • https://hyosungulf.com/uploads/file/89049788129.pdfIn PDF document text
    • http://csc0512.com/userfiles/file/20210906035510_0fipn2.pdfIn PDF document text
    • https://tramhuonghanoi.vn/upload/files/24518907327.pdfIn PDF document text
    • http://ayurveda-shiatsu-qigong-nice.com/upload/files/5802625601.pdfIn PDF document text
    • https://at2-turbo-j3t.com/contents/files/rarugajapofugudunuwelefu.pdfIn PDF document text
    • 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_off0000f14c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF14C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001095e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1095E 19588 bytes
SHA-256: 08bb9227d93c83f72bc1c6045447e4e7955a4db3073c5d675cc8c33fc6e861b7
font_02_sfnt_off00013a98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A98 10540 bytes
SHA-256: 612796bd00ab28f059463d55c4afdd317fb9c726c895d337911cf093152a9302