Malicious PDF — malware analysis report

Static analysis result for SHA-256 3780c45a8ed540e1…

MALICIOUS

PDF

79.1 KB Created: 2021-08-25 12:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 6c83cbc3420df74150b88da966a37e6b SHA-1: 790933cfef4320b90fe3744b4523210305012f88 SHA-256: 3780c45a8ed540e127042eb38812d31923651053b5d54e8cadb04e0e3a08b62b
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains a link farm pointing to multiple compromised WordPress upload directories and other disposable hosting sites, suggesting an attempt to distribute malicious content or conduct phishing. The presence of numerous external URIs and the 'link farm' heuristic strongly indicate a malicious intent to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://bsp-oblspl.org/ckfinder/userfiles/files/baditaduz.pdf In PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/5c3f39527c9d2eaf66734bbd2b2e7f8e/ronadari.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a8d71afba---81512600693.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/43890275412.pdfIn PDF document text
    • https://infotechb2blite.com/bot/ckfinder/uf/files/56626529756.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/66152447510.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/25023693179.pdfIn PDF document text
    • https://inijariku.com/ckfinder/userfiles/files/39959781546.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/1019f2454df8c47c563bfb5ca7dd2003/nuboxategarofizijivifubul.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210610190153921081333.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/fewul.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d438548a6a---jawegufavupeluwekosiri.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/wojekanilarefitiwo.pdfIn PDF document text
    • http://hurtmar.pl/Upload/file/nedopevitivofabalefive.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/8c27a466c0006012eb6345ee174a1dd0/logidejivufo.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160f223626a91d---19539756998.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/14995578071.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c117396da3c---19730050371.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/jotusojisusibivux.pdfIn PDF document text
    • http://dichvutot99.com/webroot/img/files/tazifaxigigovegexepatabu.pdfIn PDF document text
    • http://langfordfinancialservices.com/userfiles/files/berujog.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed87e31d7a1---8526275690.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/n0ldu293mjpar388har7kg6ds0/dirorumusomuwexabu.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16109dc94708d4---nuruterukologeven.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=trainer+hero+empires+and+puzzlesPDF 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_off0000d062.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD062 16772 bytes
SHA-256: 214776b852a11ea9bb3a19559a35baa0aad78b9233966d78ab02e12fe9c4f898
font_01_sfnt_off0000fbe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11400 10680 bytes
SHA-256: 7798265566664ee38eac448871042a1d8507b9fcff5160b405b8a0d305722255