Malicious PDF — malware analysis report

Static analysis result for SHA-256 551609accf557ded…

MALICIOUS

PDF

81.6 KB Created: 2021-09-03 22:56:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cb4e98e5fb216702e00cfb6c01a7a240 SHA-1: c0164a42c83aa45c612806c948cd270097b15078 SHA-256: 551609accf557ded275c3d196eda074a88e16fbe3c518f59ef18a821b48a63d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to direct users to malicious sites, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 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.
  • 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://nazrabilisim.com/calisma2/files/uploads/77609544269.pdf In PDF document text
    • https://detectiveoffice.net/userfiles/file/wakipubomezitujo.pdfIn PDF document text
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/33233404708.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/21750207554.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/sazebomijexetukixusuvoga.pdfIn PDF document text
    • http://kowalstwwo.pl/public/cms/images/file/pawowarixidusebureviso.pdfIn PDF document text
    • http://sgadsahodayatarntaran.org/sahodyatarntarannew/userfiles/file/xukivefori.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160865c9d3766c---99198900038.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a991f1de94e---momibetaxinagotinav.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/divawetedafuxorawojol.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/pogifoje.pdfIn PDF document text
    • http://sns.hu/_user/file/xofakedelolel.pdfIn PDF document text
    • http://constantemail.com/userfiles/file/1623535360jodakejirizuvafuvepadowa.pdfIn PDF document text
    • http://blackivy.pl/userfiles/file/9242522453.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/q33ofkin29q2sndtnkapbfeni0/74880084942.pdfIn PDF document text
    • https://anfauglir.com/images/file/woworogiluzodeturonaworig.pdfIn PDF document text
    • http://yournamebadges.com/withyourdog/cms_uploads/file/12229987258.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/df5ba9fcfad11c71d4c9566c99dc7a0e/vovorasubabajodulijuv.pdfIn PDF document text
    • http://alptw.com/images/files/21903263796.pdfIn PDF document text
    • http://119pump.net/d/files/27051711327.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/zofizobetemukel.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1612377685a009---nidaw.pdfIn PDF document text
    • http://assistance.uz/images/shared/file/rasexezeranedomifusiw.pdfIn PDF document text
    • https://fsbulletsandbrass.com/userfiles/files/43420011598.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=future+perfect+tense+vs+future+continuous+exercises+pdfPDF 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_off0000d9b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B7 10648 bytes
SHA-256: 199ddaa09689649cd609b72b0597ecafdd94240210654538ed3e001c12c055f7
font_01_sfnt_off0000f241.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF241 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A53 17772 bytes
SHA-256: e46484378b2960cb136a2fb28b56dcdd43f38745db5c0d1f0ca577a4f60e3264