Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7aac9bb3325f460…

MALICIOUS

PDF

101.9 KB Created: 2021-07-04 23:05:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b0005b68d1d199b1918c395fd088f949 SHA-1: e086df15d1b3f32039a7cad5e008b71e10b64343 SHA-256: b7aac9bb3325f4600856f7b56f3b493bd2d9094ef411efdb00b6a425bf652e8a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to compromised WordPress upload storage and other disposable hosting. These links likely serve as lures for phishing or to distribute further malware. No scripts were extracted, but the PDF structure and URL patterns are strongly indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9938

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://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160defd53640c2---54008377812.pdf
    • http://kiuruvedenlukio.fi/tiedostot/file/vuvapaliresikomiziwelep.pdf
    • http://nemdanangpho.com/uploads/2021-06-10/images/files/62340088838.pdf
    • https://unique-u.biz/images/uploads/file/levezimaxanabilopa.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ee3b591ec---soperekokebom.pdf
    • http://dentish.ru/ckfinder/userfiles/files/lubinogadojos.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1fa4896a07---fedora.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/bdca1f4b67aba1e332aff7653a895045/26150340301.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/44ade2cb8a5b3fadd4e383766ec6b108/92844620087.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/e188901eaaf785871123415de340bb06/nukizozefomitoma.pdf
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/1420abfd57c4f7be73e1b1f6065ea3d7/nunepabivabikexutuwulofi.pdf
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c8deb123ce3---vujetojatipedizo.pdf
    • http://bigsvatcharasith.com/userfiles/file/65692239371.pdf
    • http://londonjip.com/userData/board/file/63379159292.pdf
    • http://nusratali.com/userfiles/files/rudodubivuk.pdf
    • http://chayka-svg.ru/files/kabasunuk.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608035f652bf1---79459841150.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd8083bdf58---lokebawonuvudo.pdf
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/c7a764fbdee19810fecca958f0a2b8af/gujupibi.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c971cb9f9ce---tomapatozi.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/117q3v8o9pp5v0i4dirjo1o9fv/55803497458.pdf
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/aa2f55b75f09e72988e425b13c53a5f8/66818095116.pdf
    • http://tamker.hu/userfiles/file/88203978632.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=what+is+the+other+name+of+golgi+apparatus
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012744.bin
653e380585aaf13e71dc9f479bf3348506d42c167335b7315b3c83a0dc0bb56e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12744 10900 bytes
font_01_sfnt_off00014050.bin
1b98bcebad5a70551a9b99bea7fa81efedca23798da308baf4caf24bd87ea283
pdf-font-stream PDF embedded font (sfnt) at offset 0x14050 18616 bytes
font_02_sfnt_off00017083.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17083 16792 bytes