Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5a62710edeeaaf2…

MALICIOUS

PDF

78.7 KB Created: 2021-09-16 06:57:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ef8af90044f777e5b141d2953bf72f45 SHA-1: fff2503c1ea3f3b9c53d328aaef7e74dce11146a SHA-256: f5a62710edeeaaf2f124b9805f0c2e504ee77e37167fbc5f6f1f226cc058ca61
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and does not provide direct user-facing content, but the heuristic firings confirm the link farm nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3d79309ad---vufanesus.pdf In PDF document text
    • http://tochalco.com/uploads/files/xodivoberutegeripuvoxi.pdfIn PDF document text
    • http://interface-referencement.com/userfiles/file/41618912027.pdfIn PDF document text
    • https://best-label.com/upload/files/79445246740.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/gizapeluranex.pdfIn PDF document text
    • http://hanilkwanla.com/uploads/files/8298925311.pdfIn PDF document text
    • http://qlionshousing.ca/userfiles/file/7025873858.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/45239455057.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1b4930f22---92345672329.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/xiroranunotojake.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/4410594987.pdfIn PDF document text
    • http://capitaloffice.pl/fotki/file/55314841267.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/82033407893.pdfIn PDF document text
    • http://dgjinhak.kr/DATA/upload/files/202109090311257632.pdfIn PDF document text
    • http://nmways.com/uploads/fckupload/file/84042527015.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613391c9b6727---pakuduzesilofa.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/lamenejegunuvosafaguka.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/namotaf.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0912e934a---18062975777.pdfIn PDF document text
    • http://1hozain.ru/files/userfiles/files/9156319075.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/7300727128.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=free+gold+dragon+cityPDF 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_off0000cf16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF16 18364 bytes
SHA-256: 64b5c356136da0654d595a3c9967e554299e220cf4ee87b4e10ddf2ac161260d
font_01_sfnt_off0000fe28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE28 10468 bytes
SHA-256: a9b100fdaa8e40a40d7ba2d15c55c674fad40a4fc4f10b449138b162e339c483
font_02_sfnt_off000115ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1