Malicious PDF — malware analysis report

Static analysis result for SHA-256 031e03c8251a8d36…

MALICIOUS

PDF

80.5 KB Created: 2021-09-06 08:42:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 284e6d3b1a93b5b13cd35acf19bc1db6 SHA-1: fc927a62df82f26a36914bfef6c39089ac5dd27b SHA-256: 031e03c8251a8d36e4502748acb6642b8ad998f4cbb0b319b79e2f521b4015b1
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 ClamAV and an ML classifier as malicious. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and embedded links indicate an attempt to lead users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607726ce1be1c---jabat.pdf In PDF document text
    • https://emmaushuis.org/pages/rikakug.pdfIn PDF document text
    • https://makiriaszto.hu/ckfinder/userfiles/files/bimuvogorowilal.pdfIn PDF document text
    • http://flightshop.jp/images/blog//file/34833990197.pdfIn PDF document text
    • http://vitrine-prof.com/files/86086498337.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/5545794521.pdfIn PDF document text
    • http://michardardillier.com/ckfinder/userfiles/files/vojilifoxuwudanosam.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/ririfoxovozatefepa.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/makesozekisofufurunabaf.pdfIn PDF document text
    • http://heatherjansch.com/ckfinder/userfiles/files/49675371218.pdfIn PDF document text
    • http://enjoy.sk/editor_uploads/system/files/liraxirilote.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/fotuzuvixigagobogelok.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/f471806a4ca97e5cdc48855fe58325d7/rupobiwogakajejipaf.pdfIn PDF document text
    • http://mayjack.com/upload/files/47106872151.pdfIn PDF document text
    • http://cafehinglung.com/uploads/files/85907883871.pdfIn PDF document text
    • http://falerisztika.hu/tmp/supuporerez.pdfIn PDF document text
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/h9brho1rjjsnvjv7hirsuo0d7s/jalupepobosixoror.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/24789542304.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c95a295f892---23203802905.pdfIn PDF document text
    • https://nhahangbienhaitien.com/uploads/files/91897600314.pdfIn PDF document text
    • http://osteriadelcampanile.com/userfiles/files/57759875012.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079d795347be---72348148806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=container+gardening+for+all+seasons+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_off0000d7aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7AA 17060 bytes
SHA-256: 8857e780c61cc2120e5b15431debd26f53e7b44f586cf89d5588d573f1e0027b
font_01_sfnt_off000103a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BBF 10704 bytes
SHA-256: 52e914e0d85ab1637a42aac36aa1564d79fa50b2e9b7181acf51c123992dcbe4