Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb44166d4108878a…

MALICIOUS

PDF

68.0 KB Created: 2021-09-19 18:34:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 03d9d6209c556f12fada2cffe099a752 SHA-1: 3320378c5a47d8865759c7e83d5e9dd92caffc4f SHA-256: cb44166d4108878a2093a65e031ba009c15c93087911fc8ae8d83df175a96c20
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier further support its malicious nature, indicating it likely serves as a lure to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • 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.
  • 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://alphasigmaoverseas.com/userfiles/file/51199076417.pdf In PDF document text
    • https://euro-m.si/web/dokumenti/file/jefum.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/58115088655.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/37315812182.pdfIn PDF document text
    • http://jumpstart.mobi/userfiles/file/gefelo.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613671d5eed59---54217235520.pdfIn PDF document text
    • http://targhevaticane.it/userfiles/files/xapefilejuvupanibusiwota.pdfIn PDF document text
    • https://clubelsendero.com/img_pag/file/dapufubevumid.pdfIn PDF document text
    • http://munnarinfo.in/userfiles/file/pesebotofagaxukovovupexox.pdfIn PDF document text
    • https://baruipur.org/ckfinder/userfiles/files/94893973551.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/vafenexibudelot.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132edd945454---giretixuxiropukowokaveva.pdfIn PDF document text
    • https://buddhaart.in/userfiles/file/jaxufidamitileli.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/mojaruluwijinisudi.pdfIn PDF document text
    • https://gelblighting.com/userfiles/files/memakelanijupew.pdfIn PDF document text
    • https://zenithoverseas.com/assets/userfiles/files/35093774822.pdfIn PDF document text
    • https://yapluka-services.fr/userfiles/file/rebidanuzupubolew.pdfIn PDF document text
    • http://studiotecnicolari.it/userfiles/files/famafuposugo.pdfIn PDF document text
    • http://www.plain-pied.com/editeur/ckfinder/userfiles/files/25037645213.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161409d433258c---riranomilabubepebopiseni.pdfIn PDF document text
    • http://mundori.com/js/ckfinder/userfiles/files/tuzifasivaweworolewoxegoz.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/6096f2f9700b3699a5ca4348cce78b50/jopawoxitekavolewe.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/topefolafadutib.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/44692011796.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=botim+download+for+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_off0000af42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF42 10356 bytes
SHA-256: 72b30674e02b678f0b8158818f3c8729882d93afc75488fd1ef722727987953e
font_01_sfnt_off0000c6a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6A3 14248 bytes
SHA-256: fde1b3e0aba71115473ea0dab5f58ca6a18414231cdf2b2fe5227c3e6c7a153d
font_02_sfnt_off0000ea2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA2B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1