Malicious PDF — malware analysis report

Static analysis result for SHA-256 a52d9a48a5b464b1…

MALICIOUS

PDF

74.9 KB Created: 2021-09-17 16:42:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e6f92d475997beb077639c0d31bae685 SHA-1: 238174d2c294fe348ac8bd353c19f43df10b921a SHA-256: a52d9a48a5b464b19ce8d7387812a27dc17a4fd94f19a908236047a3789b53eb
166 Risk Score

Malware Insights

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

The PDF contains numerous links to external PDFs hosted on various domains, many of which appear to be disposable. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a pattern of distributing malicious content through a link farm. ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious nature of the file. No scripts were extracted, but the structure suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://mixmarketing.vn/upload/fck/file/37093013205.pdf In PDF document text
    • https://larrialdiak.es/files/galeria/files/gikinunutedulazotubipit.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/53365323806.pdfIn PDF document text
    • http://porpora.eu/imagenes/imagenes_contenidos///xuvebupo.pdfIn PDF document text
    • http://ambulatorioveterinariovianello.eu/userfiles/files/53774994656.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161429472c2131---96328343351.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/52271339464.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210904005044383666.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/poxilokemotigaguzirubo.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/8185311623.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16139bbc3e1863---69130660370.pdfIn PDF document text
    • http://ramenzoni.eu/userfiles/files/bijifibeduviluzez.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/jelokikoxibitesetav.pdfIn PDF document text
    • http://tivatijapan.com/uploads/userfiles/file/54586829597.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/14487668871.pdfIn PDF document text
    • http://yameitecl.com/ckfinder/userfiles/files/20210901_074554.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/levorazo.pdfIn PDF document text
    • http://majedalkarkhi.com/pics/file/zakelemiz.pdfIn PDF document text
    • http://churchontherockuk.org/home/churchontherock1/public_html/userfiles/files/62358828968.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/25323672589.pdfIn PDF document text
    • http://cee1968.com/ckfinder/userfiles/files/79072664275.pdfIn PDF document text
    • http://veganogle.es/uploads/ckfinder/files/lilenopa.pdfIn PDF document text
    • http://ms-beauty.com/ckfinder/userfiles/files/84947874002.pdfIn PDF document text
    • http://graczeonline.pl/userfiles/file/32623584413.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/nizebibikozedokozas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=skull+wallpaper+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_off0000c07c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC07C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD893 10580 bytes
SHA-256: ca1130e963b13b00e9c503c28b6b1e3c879b4501a9382da18eee415f7415c8ac
font_02_sfnt_off0000f0e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E1 17180 bytes
SHA-256: 58478f1a9fb62931334b579a83667a820a6f55045800ec2ab6f5129c14b3b4a2