Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8104b824cb9f7b0…

MALICIOUS

PDF

80.9 KB Created: 2021-09-10 05:35:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 55e90cfa513244a45d11d23405120e4b SHA-1: 6844d8b89967720eeb484358c3049f0b38370c87 SHA-256: a8104b824cb9f7b0de0e008ad93f0c402397665808139711caa540c3d08130e7
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious. It functions as a link farm, containing numerous URLs pointing to external sites, some of which are hosted on compromised WordPress installations or disposable domains. The presence of these links suggests an intent to redirect users to phishing pages or sites hosting further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://xn----7sbbbizu2bxaod.xn--p1ai/userfiles/file/62914597868.pdf In PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/16e239c27c6754beb0a98f9a1dad9a37/xoganati.pdfIn PDF document text
    • http://dymenahealthcare.com/upload/fckeditor/file/7332595725.pdfIn PDF document text
    • http://5thaveseniors.org/userfiles/file/78819259086.pdfIn PDF document text
    • https://rafaellopezehijo.com/upload/files/42776070927.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/zujuxixaj.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/6defc601100f780e6dcfb091c4823eca/xubawa.pdfIn PDF document text
    • http://b40555.handyfriendship.com/upload/files/89120684286.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec62ac844b---ruziwugixilamuluvuxalupuk.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/kanuboba.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/22859382689.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/bedb57fb5e97f656bf36f47972701e96/58373944074.pdfIn PDF document text
    • https://combrooncom.com/contents/files/39259194289.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161314b8067200---zewosujubudunavu.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/dulefopol.pdfIn PDF document text
    • http://roberlo.cz/www/files/file/vatopajafojojafotif.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16134a0411ead9---31386714274.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc692bc1e3---kopemutubusarulonirepuni.pdfIn PDF document text
    • https://hockeymro.ca/docs/file/gegodalogufigezeg.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/17519112301.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109030518278537.pdfIn PDF document text
    • http://graphicyazd.com/ckfinder/userfiles/files/dutibapiguxejepatusolidig.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/70196315486.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=snake+eyes+filmPDF 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_off0000d926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD926 17588 bytes
SHA-256: ff92e0cc8db702b81b10ee16dbe5d8a6f0a5b46f4a2594fc861220ef25bd028c
font_01_sfnt_off000106d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011eec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EEC 10336 bytes
SHA-256: c95a7cba1787d602fbbae688f4024314d0bbf2a5566a809fb4867aa2f7735299