Malicious PDF — malware analysis report

Static analysis result for SHA-256 c51f2035c65fd3de…

MALICIOUS

PDF

73.6 KB Created: 2021-09-29 04:19:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: f49ed39c0b86cf5ef48701b9fa9e518f SHA-1: 636b44a09205cc7b9507878044336feff72fdd24 SHA-256: c51f2035c65fd3de9cb011b1db22dca0e515aa8a89721085fc3e2516fd73bdce
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common tactic for distributing malicious content or conducting phishing. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs suggest an attempt to redirect the user to a compromised or malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

Heuristics 5

  • 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.
  • 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://speckrepeg.by/UserFiles/files/tajozosegewesanunumikasax.pdf In PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161446fa5366a5---xusodaterulaluf.pdfIn PDF document text
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/lelanojosotol.pdfIn PDF document text
    • http://chinahk-ip.com/chinahk_ip/html/files/editor/file/nabosimaderemonovov.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/40431865677.pdfIn PDF document text
    • http://caramelitos.sk/files/67283440069.pdfIn PDF document text
    • http://cen7dias.es/userfiles/files/94269159966.pdfIn PDF document text
    • https://wanfutemple.urwaydesign.com/data/file/userfiles/files/kajobexar.pdfIn PDF document text
    • http://xhiehchin.com/Xhieh_News/_file/rupasuzuforonuvup.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/jimirafakofepinepurosir.pdfIn PDF document text
    • http://debsecond.net/UserFiles/File/32731312322.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/33362049567.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/378aa300d2917978ed28d724c2f30d9b/57581032825.pdfIn PDF document text
    • http://autosklo.sk/pictures/file/85692924611.pdfIn PDF document text
    • http://hflchw.com/upload/file/fafatilawetuke.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/16143d92ca0338---3049475885.pdfIn PDF document text
    • http://sissonne.hu/editor_up/lipar.pdfIn PDF document text
    • https://pjkconstruction.ca/images/file/gujefipoxavafegumuj.pdfIn PDF document text
    • http://satthachkhe.vn/image/file/41617809826.pdfIn PDF document text
    • http://csa.china-led.net/static/editor/ckeditor/ckfinder/upfile/files/5873932457.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/nedirilila.pdfIn PDF document text
    • http://placidlakes.com/larpm/uploads/file/boraduwaduban.pdfIn PDF document text
    • https://muacash.com/webroot/img/files/98718933887.pdfIn PDF document text
    • http://labemweller.medianet-shop.de/userfiles/editor_files/file/fobamebiwadawolelewura.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/jilixofizutatojudex.pdfIn PDF document text
    • http://myphamasia.net/upload/files/golifekawokimelovoki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=apde+android+processing+idePDF 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_off0000b904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB904 18500 bytes
SHA-256: dead76900e51c4a9a06d8f34ab387a6d63ccf74e425c16c0933f7b101795550c
font_01_sfnt_off0000e874.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE874 10528 bytes
SHA-256: 58e82a759cbaa063303ea7658ee188f11d1f631cb65567483bc96cfbea1bd1e2
font_02_sfnt_off0001004f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1004F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1