Malicious PDF — malware analysis report

Static analysis result for SHA-256 27fdc9d2f0f1ea16…

MALICIOUS

PDF

81.2 KB Created: 2021-09-07 18:05:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a3f2ce260271b158dac1b0541853346a SHA-1: 8b830b7c230ed1c54291c413399a4d1b326a2ae7 SHA-256: 27fdc9d2f0f1ea167203bd897bb920f3c59285083e748b9a7d9d27286407eb94
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 0.9960

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://www.andreivieru.com/ckfinder/userfiles/files/newipubumibekufajabip.pdf In PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/06158e02652eb4dda963f54c19b28c0d/6230033041.pdfIn PDF document text
    • http://cathayred-csr.com/img-cathay/files/90464884517.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160837a8d5befb---77042791205.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16077f7ce372f6---tufobeb.pdfIn PDF document text
    • http://ff-engineering.com/userfiles/files/58841496512.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/f4q0o3gg1h3kbtnfqm01vru8j1/31357022073.pdfIn PDF document text
    • http://e-photo.lv/ckfinder/userfiles/files/58978045350.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/xujonaxenenavod.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d338b4c0f7c---noraluxojola.pdfIn PDF document text
    • https://kristinanamaste.eu/files/17201899390.pdfIn PDF document text
    • https://www.sterlingsez.com/ckfinder/userfiles/files/bozitasasebedamiralum.pdfIn PDF document text
    • http://kennycojewelry.com/userfiles/files/202107/1627167004.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/21520689238.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/36768128741.pdfIn PDF document text
    • http://erisalaw-chicago.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/20806766867.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/76185707897.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/7tt3a678p85ksm33uq16qpqmmb/3541214014.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/lewukejikugizatekim.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/3dd234f59bd61cc85e857145c5115273/bokitutupuvemofatid.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4fb61b4e6---72015690994.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/aee64aa86bb9f0e637814cc46d6443c8/wutumafabexizoz.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/64371316591.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=english+writing+worksheets+for+nursery+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_off0000d6dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DD 17900 bytes
SHA-256: e3598162dcf482f0f76e0aa2a1fb75a72fa2d549f8cd32645ce99dc21dbb9b0a
font_01_sfnt_off0001059e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1059E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011db5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB5 10992 bytes
SHA-256: 3b2761c6a0b618606ba77ea77fbb0fcbd0375ec6acf136027853cf209b8ede93