Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a68437640c46d1e…

MALICIOUS

PDF

84.3 KB Created: 2021-08-31 21:15:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: d3f10f794d35d927caf3be83f649888d SHA-1: 07f8295d3cb6cde3a0c5d666482a327101b6c2c1 SHA-256: 5a68437640c46d1ef837972d9c808d5b9ab81e8494de067cfaf426e2c277ca8f
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ctners.com/ckfinder/userfiles/files/45575561674.pdf In PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16083e43e93b25---5007897052.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160793d0c7dce1---906752174.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b54aeebe8a0---lumidabur.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/e3a84603815be3933c1301a0c36c2afa/viroduwenute.pdfIn PDF document text
    • https://valubil.com/public/uploads/cms_file/cms_files/78977869585.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9ef52a004---bedilovigixedenopudi.pdfIn PDF document text
    • https://yesilkoyluleriz.biz/resimler/files/fusalusizixenerun.pdfIn PDF document text
    • http://stilistspb.online/public/files/uploads/files/lopadotumezasevepevu.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210716022341_m5g8pp.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/6leoh8apnpgv1c245vss86grlm/94690152255.pdfIn PDF document text
    • https://aordonez.com/images/contenidos/files/86457025783.pdfIn PDF document text
    • http://technocom.pl/editor/file/pepegoserabemidolemen.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160896a9e12912---vepizubunobarudax.pdfIn PDF document text
    • http://studioguidobarbieri.it/userfiles/files/6468390021.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/26585961131.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/dawawubuwuvotufogifamede.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16119abb167874---xagire.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c9828e78832---rujulutagaxifupinike.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa82ed584d---diwarojukibube.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610fa730371a8---3458207280.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/97913337850.pdfIn PDF document text
    • http://police8coop.com/UserFiles/file/sanarosizagokufikota.pdfIn PDF document text
    • http://thetownsendfamily.net/clients/a/ab/ab79602242cca8f930cd52af13df1d51/File/kuwepoxutemonemuni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=soothing+food+for+stomach+ulcersPDF 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_off0000e4ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4BA 17152 bytes
SHA-256: 2381a1f8c6742382fa27231d19525ca0dbb1cbf5d741c3af64401e78226a27d1
font_01_sfnt_off0001114a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1114A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012961.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12961 11096 bytes
SHA-256: 35a3ffee3243e0d797cf6c60388249d5a24c9b55bee2d349bd768503576eeaef