Malicious PDF — malware analysis report

Static analysis result for SHA-256 66c4d63a07de1c91…

MALICIOUS

PDF

68.0 KB Created: 2021-09-15 21:58:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4cb0528bcd5ce03a5e01bd1091e7e1a7 SHA-1: 3a5958885aa59af1b986e8315bff97b9c50ba70d SHA-256: 66c4d63a07de1c91870ff013466e6abeddae231d31395a1a4fa1ebfe45ac3361
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://archism.ru/uplcv?utm_term=the+long+drive+free+download+android PDF link annotation
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a151ccb476---8696354901.pdfIn PDF document text
    • http://hzkontejnery.cz/ckfinder/userfiles/files/30017550798.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1630711558.pdfIn PDF document text
    • https://trouver-une-ssii.com/img/pics/files/45375699855.pdfIn PDF document text
    • https://horgaszvelem.hu/ckfinder/userfiles/files/xiwanunemijudelaxele.pdfIn PDF document text
    • https://pgprojekt.pl/Upload/file/jigeworemokibu.pdfIn PDF document text
    • https://ambalatender.com/upload/files/walexewimipefesixufozenu.pdfIn PDF document text
    • https://eminentland.com/admin/userfiles/files/gugejozigiz.pdfIn PDF document text
    • http://michelesherrinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/15628464354.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161411610b8c0f---14023712107.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/23727916073.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/88504374690.pdfIn PDF document text
    • https://newtop-eg.com/userfiles/file/nejunov.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/obnvr82m9eqvhkfl4eauhntid4/bisajafononubevapugiwe.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/fojek.pdfIn PDF document text
    • http://dietetyka-24.pl/images/files/vidokeg.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/legotekalopuzuzagonun.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161380b844561e---fifijidev.pdfIn PDF document text
    • http://hermandadperdon.es/userfiles/file/22479976116.pdfIn PDF document text
    • https://aukshanya.promosing.com/alpha/ckfinder/userfiles/files/40869571552.pdfIn PDF document text
    • https://minlinart.com/archive/upload/files/37596175164.pdfIn PDF document text
    • http://tieclangman.com/Images_upload/files/vajurutelekiv.pdfIn PDF document text
    • http://kristiankutschera.de/userfiles/file/31925006308.pdfIn PDF document text
    • http://www.focitabor.hu/userfiles/file/14211162449.pdfIn PDF document text
    • 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_off0000af51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF51 14444 bytes
SHA-256: 04402f765bb8927a9228931bc5d15267614de5bdc75dd8789bfdd680ab1704c6
font_01_sfnt_off0000d2ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2FF 10484 bytes
SHA-256: 9adc02b3d0d095cbdfac158831e8cbb8bb3dc7c52bdd31006926addc51b0ccfd
font_02_sfnt_off0000ea96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1