Malicious PDF — malware analysis report

Static analysis result for SHA-256 68d36384ba9b3cb3…

MALICIOUS

PDF

137.6 KB Created: 2021-09-08 00:49:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: eef6e5aac9f9cc69de15fd6cff8119d6 SHA-1: 078b5026d96b8f16bee0a833930e621871ffa484 SHA-256: 68d36384ba9b3cb31e67db057cf751e4a0851bf6894f334d51142543b27700f8
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9871

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://chunmianxian.com/upfolder/e/files/20210616005949.pdf In PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/d872b7a43466e52a60f5d361a8e51b11/wofatit.pdfIn PDF document text
    • https://advertisementnepal.com/ckfinder/userfiles/files/jabuxakususisu.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/hpkn6un38hp4ki14a0opshudtq/kapoferefobetuxujut.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c4fb444ac321365f8eda0c987d15106e/91514988698.pdfIn PDF document text
    • http://sanchariglobal.com/userfiles/file/76463175665.pdfIn PDF document text
    • https://kebecelectrique.com/upload/editor/file/kasowelazijif.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/patosefesokan.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/lebegox.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/35816233390.pdfIn PDF document text
    • http://rspon.pl/images/wyswig_images/file/vezadokerafiwumefug.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608952c4e45ca---jikefomawi.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/7h8h6p7f2ciejeglcb2b1atp4k/nozibozanevumusewidi.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/2c64f6540818df571e00ba9b2d2ac5d4/6582854297.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/gajinuvax.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/juzejapobaju.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16085ac8610ac8---8600481967.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/87425742271.pdfIn PDF document text
    • https://okna-kursk.ru/page_edit/_samples/userfiles/files/12625122977.pdfIn PDF document text
    • http://yilip.net/userData/board/file/51447837091.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/hjn31922sqh66s0f637ou0heis/6216538686.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/72260138578.pdfIn PDF document text
    • http://naturallabs.fr/userfiles/file/xuginavi.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/idanipvrdpj33d75hfpcthd3q0/mikiwezofet.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/turojevi.pdfIn PDF document text
    • https://digitaldaya.com/imagenes/file/82782010626.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=whirlpool+double+oven+gold+series+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_off0001b8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B8C4 11040 bytes
SHA-256: 7377f77e6d64a23d391670ace02e6ae449c4d173e511bf02dd32099f05a5a024
font_01_sfnt_off0001d1c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D1C2 17644 bytes
SHA-256: 52a487db3fd069876b8e4a1d48e61e9a9cfa1ad2cf9467827b54703be6b8a01c
font_02_sfnt_off0001ff86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FF86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1