Malicious PDF — malware analysis report

Static analysis result for SHA-256 9624fd71c7bbfb63…

MALICIOUS

PDF

80.2 KB Created: 2021-09-04 17:25:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 622f499266e94a65085bd860345e8612 SHA-1: 6c1b563c28d5455031c32396e9ae25cab52e32b5 SHA-256: 9624fd71c7bbfb63652bd498d5b76f71640b837212b00f579c1ee56998a80086
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The sample is a PDF document that contains numerous links, many of which point to compromised websites or disposable hosting. The 'SE_CLICKFIX' heuristic indicates that the document likely instructs the user to execute a command, a common tactic in social engineering attacks. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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://ukicda.com/admin/fckeditor_upfiles/file/2021060906133680554.pdf In PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b0ac1cb9885---40661350347.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/7963239708.pdfIn PDF document text
    • http://pelejas.com/IMAGENS/CKFINDER/files/gujikuxabak.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5442ca16e---nexeribezalojikosik.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/vanigoliwavorezanove.pdfIn PDF document text
    • https://nhachoxebus.com/upload/fck/file/79275058929.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1e222cad8---54022526948.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/64902079623.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609971376d48c---nokape.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/pnvvlo7iedjqnc248gvjdnqt3n/zirilinazedarowafevixif.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/3829547183.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e8c66da1a---23630272048.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/wulepawekinoputa.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086a92699399---levaju.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/647a47893858c9ffcabd610ffce83ede/86136331600.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607131ad8a78b---20519253956.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ac5173f3c---9739162259.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160834a7ee4dba---dogumenekuwegekedawamak.pdfIn PDF document text
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/abc83302695bf43f9bbf1fd9fbd41822/88520458937.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce3b688b3e6---39189300489.pdfIn PDF document text
    • https://dunakanyarfesto.hu/ckfinder/userfiles/files/kobazefanepoko.pdfIn PDF document text
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/99544110390.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/83753629048.pdfIn PDF document text
    • http://kbchina.de/upload/filarakikalipodaxexanofus.pdfIn PDF document text
    • http://malopolskiszlakwinny.pl/upload/File/fizuwejosorosinozokogatu.pdfIn PDF document text
    • https://menu2uplus.com/images/file/fasobavavilefigopisojeve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=4100es+fire+control+panel+manualPDF 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_off0000d78d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD78D 10896 bytes
SHA-256: f272a7356af8117caefd282e6204041b0a56831087261df85af11487a7c307e4
font_01_sfnt_off0000f0c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000108da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DA 17092 bytes
SHA-256: 64716e3e4151385b8fc0597693e7a3d24c28f5d8f935daba4e2fa4e2a6d679b0