Malicious PDF — malware analysis report

Static analysis result for SHA-256 c371ff358b521844…

MALICIOUS

PDF

84.1 KB Created: 2021-09-23 04:25:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: e69e3b797b68af5c09f817441576870f SHA-1: 9ec902a41ac5997c077831ef5426f01d7c357c74 SHA-256: c371ff358b5218445129d5a39b84bc2aad2070e9d8e6aef43d0ab4490fef86ef
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users. The high number of external URIs, many pointing to disposable domains, suggests a link farm or phishing attempt. ClamAV detection and ML classification strongly indicate malicious intent, likely to deliver a secondary payload or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chupanhnoithat.vn/upload/files/nuwofolijasijiverejawidir.pdf In PDF document text
    • http://majedalkarkhi.com/pics/file/3679290881.pdfIn PDF document text
    • http://eko-baby.ru/userfiles/file/gomuwoxubonalonenubukez.pdfIn PDF document text
    • http://naasschoolofmotoring.ie/fckeditor/userfiles/file/77834574801.pdfIn PDF document text
    • http://abwmechanicsville.com/uploads/files/43125896435.pdfIn PDF document text
    • http://mgtofubbq.com/uploads/files/voxowumikabomoguriguke.pdfIn PDF document text
    • http://flapboxes.com/userfiles/files/tajuwetaduriridiga.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/19466809475.pdfIn PDF document text
    • http://tylincms.com/userfiles/files/31300910109.pdfIn PDF document text
    • https://ecohort.info/userfiles/files/zobesarenij.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///75387773269.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/23727979811.pdfIn PDF document text
    • http://somsit.com/ckfinder/userfiles/files/37945238689.pdfIn PDF document text
    • http://belstroyiz.ru/img/file/virim.pdfIn PDF document text
    • http://it-hair.com/userfiles/98419841850.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/50741181641.pdfIn PDF document text
    • http://daieimotors.com/js/upload/files/zafewa.pdfIn PDF document text
    • http://bippex.com/filespath/files/20210917083408.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/83658674125.pdfIn PDF document text
    • http://museodegliarazzimarsala.com/userfiles/files/fopibenas.pdfIn PDF document text
    • https://sayurhijau.com/contents/files/27392900562.pdfIn PDF document text
    • http://kedehg.com/ckfinder/userfiles/files/44632884072.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/gawasinapozizizi.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/64436199435.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/xarajujo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+stop+message+vibration+on+androidPDF 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_off0000e214.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE214 18024 bytes
SHA-256: 4b274029685d580eddec5ebc51d85f39c3ed2fb97a2d340bc20c9cba1dfd61c7
font_01_sfnt_off00011104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11104 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001291b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291B 10972 bytes
SHA-256: f8452633cce8015566f84c1c6b556527078daa7edda4f2c41ae8646ec6089f9a