Malicious PDF — malware analysis report

Static analysis result for SHA-256 f634ab006bc5fefc…

MALICIOUS

PDF

81.0 KB Created: 2021-09-15 22:20:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 54a00125e160afca0458423e3a72c679 SHA-1: 7af78f639d14c17269dcf6e84e2e9757ba49f4c0 SHA-256: f634ab006bc5fefc9166bce6ec9342871662de2925a2287bbef75a1246766f50
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also contains numerous external URIs, many of which point to potentially compromised websites hosting further PDF files, suggesting a link farm or redirection mechanism. ClamAV detected this as Pdf.Phishing.Trojan, and the ML classifier also flagged it as malicious, indicating a high likelihood of phishing or malware distribution.

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
  • 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 https://www.xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/sesulabidati.pdf In PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/51608126516.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/2tdd0akuktlfsl6h581cijbujn/18834817962.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/41023243617.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/xetikapojibapofanuraxivov.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/96066862869.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/jubokiwesaso.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210907174409297286b1fo0e.pdfIn PDF document text
    • https://silatur.com/js/ckfinder/userfiles/files/85093941435.pdfIn PDF document text
    • http://msinziniering.com/userfiles/file/77035328979.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/99855565796.pdfIn PDF document text
    • http://auto4-spb.ru/public/images/ckfinder/files/gogig.pdfIn PDF document text
    • http://csigikes.hu/admin/fck_upload/file/51715818458.pdfIn PDF document text
    • https://mountmoriahcamp.com/media/45771121556.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/44501303691.pdfIn PDF document text
    • https://granitnet.hu/editor_up/wokiwome.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/xibudi.pdfIn PDF document text
    • https://www.icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/pomedifajogisufoj.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/toburazurifil.pdfIn PDF document text
    • http://smingames.com/ckfinder/files/96791480999.pdfIn PDF document text
    • http://tnetimes.kr/upload/file///semabuzovidev.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a483dac599---xuxufokelonej.pdfIn PDF document text
    • http://skisun.it/userfiles/files/betamefatonev.pdfIn PDF document text
    • http://velo.hu/UserFiles/file/kelorasumu.pdfIn PDF document text
    • https://bandotrading.com/uploads/file/44833018292.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=not+enough+storage+space+when+moving+apps+to+sd+cardPDF 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_off0000d753.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD753 17048 bytes
SHA-256: 449e0f67c2767d53443a9744dce1e293038aa7fe07f1ebdfee90c77bfb58637f
font_01_sfnt_off00010386.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10386 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B9D 11144 bytes
SHA-256: 7bdb6cc282b4939161cb993ab6b325b18fb88b3e33eb7075e5620dd9b3a7ca77