Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e3104bb0f64168…

MALICIOUS

PDF

84.8 KB Created: 2021-09-20 12:04:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: dfd0eceae0171bbe3503ba324f2750b9 SHA-1: d12622588630c74836a5abc0278004cf94209071 SHA-256: 51e3104bb0f6416854eb71ef1a69413715d52027f2fe6dafc1e84d82dec8388c
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to download pages, disguised as legitimate game downloads, which is a common phishing tactic. The presence of multiple compromised CMS upload links and disposable hosting further supports this. No scripts were extracted, but the heuristic firings and URL analysis strongly indicate a phishing attempt.

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 http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16131487aee8b1---38289613775.pdf In PDF document text
    • https://krossi.ru/images/content/files/57493604158.pdfIn PDF document text
    • http://lindendirect.com/ckfinder/userfiles/files/13640940753.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612f43a8eafbc---51780022078.pdfIn PDF document text
    • http://trieuduong.com/images/Download/zimibujevifomobo.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/b76120laclsdv6va5t8ic3h5l4/41534870602.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/kijabinimofur.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/jakuxezelama.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/robevoxaxinoteniwom.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/60095227829.pdfIn PDF document text
    • https://angel-juicer.com/FileData/ckfinder/files/20210914_05F95BEE8E3ABBE2.pdfIn PDF document text
    • https://hirurgija.me/files/19320600772.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///wulilujitexasike.pdfIn PDF document text
    • http://nusratali.com/userfiles/files/manofezi.pdfIn PDF document text
    • https://www.ruchya.com.tw/upload/files/dopilusejaziwazilokitel.pdfIn PDF document text
    • http://akademia-jedenastka.pl/zdjecia/fck/file/88396251312.pdfIn PDF document text
    • http://xn--oy2b9bv81anouola.com/upload/file/202109090007000947.pdfIn PDF document text
    • http://kleiberit.ru/files/file/62629702988.pdfIn PDF document text
    • http://4els.ru/uploads/images/files/kavetagetomosedezom.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e2b334bea3---8666180954.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/60076041107.pdfIn PDF document text
    • http://oembag.com/uploads/files/202109022329042192.pdfIn PDF document text
    • http://rocb-ap.org/file_media/file_image/file/bazesanabososokutogexewo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=download+marvel+contest+of+champions+modPDF 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_off0000dd64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD64 20740 bytes
SHA-256: 75196466e676170d318d8f11af66e0412e0a2745d7ddede95fed754ac32283cd
font_01_sfnt_off0001139a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1139A 11040 bytes
SHA-256: 1d4cb002fbcae49c978e0f55266282c782c3543893dce9c5f00f1a7bf09d3342
font_02_sfnt_off00012d21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1