Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4920de86ac80b99…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 00:56:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bfb02f8dd264d55b1a81f40cad8a0ab0 SHA-1: cb8b669a63c45a19317f8c58ddd08cfe0dd8e5b9 SHA-256: f4920de86ac80b995bdc7e89c7816b063a59a22db31f8aba515a3867d8462c0f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to link farms on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common technique for executing malicious code or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 http://clubselectionvoyages.com/images/file/51106309339.pdf In PDF document text
    • http://bikaji.zohukum.com/ckfinder/userfiles/files/76814656473.pdfIn PDF document text
    • http://gsmontaggi.it/userfiles/files/miwupil.pdfIn PDF document text
    • http://kurskodkb.ru/page_edit/_samples/userfiles/files/podupuzopukixozirekamid.pdfIn PDF document text
    • https://xcheck.vn/uploads/userfiles/file/kixebevijugelo.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021091021032374.pdfIn PDF document text
    • http://girlstown.org/files/js/ckfinder/userfiles/files/dozepubudamojewaziporuzax.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/21059901132.pdfIn PDF document text
    • https://reha.bg/content/upload/file/63363436630.pdfIn PDF document text
    • http://gma.ge/admin/ckeditor/ckfinder/userfiles/files/mawuruvisotoxuradobujot.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210904012727.pdfIn PDF document text
    • https://mobilieroccasion.fr/uploads/file/56599771248.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161385f12d367e---27816055544.pdfIn PDF document text
    • https://rafaellopezehijo.com/upload/files/84559337337.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/jadumejisofalejukibobujav.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///senutabunipa.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/bubenatofajoji.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/93801253295.pdfIn PDF document text
    • http://menifee.hanasushichoice.com/uploads/files/forukogo.pdfIn PDF document text
    • http://tyros-club.de/userfiles/file/65803329179.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/gavuwotimejiwanis.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/xokowuf.pdfIn PDF document text
    • http://hiredriver.com/uploads/assets/files/37767263269.pdfIn PDF document text
    • https://pesonabali.dswip.com/ci/userfiles/files/80540417462.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/31213182831.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/tudususuxog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=miui+mi+a2+litePDF 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_off0000da5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f274.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF274 9988 bytes
SHA-256: a70138b1582367ccdc7f241852dbd4550a49a1b4785419e45ba0b21dfff07373
font_02_sfnt_off000108a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A3 17824 bytes
SHA-256: 2990929d0d3c790b6dcd213287fc24dbdaa016ed1488e2bd2df2e41cd6a357da