Malicious PDF — malware analysis report

Static analysis result for SHA-256 57ff7c71c6911b3c…

MALICIOUS

PDF

80.8 KB Created: 2021-09-18 09:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 586ed57cd8baced1fd6ca124e3d5b6c1 SHA-1: 17a3689f16ee710b9ba8e8ac167a6e4efbac8e76 SHA-256: 57ff7c71c6911b3cd311684106e89e4ec59aa2aadd3f932d3ed82bd4754da2dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to distribute malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://easternresources.net/ckfinder/userfiles/files/pafenorinidurap.pdf In PDF document text
    • http://rickgrisolia.com/userfiles/files/56337519067.pdfIn PDF document text
    • http://nigerseedindia.com/uploads/ragumosewesem.pdfIn PDF document text
    • https://allcondosales.rodeodrivecondosale.com/userfiles/files/dasinadefetaliwori.pdfIn PDF document text
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/23413481951.pdfIn PDF document text
    • http://x04ydivan.ru/userfiles/file/10026907596.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/tugoxukuduz.pdfIn PDF document text
    • http://hocomesun.com/upload/tovifulofalotikomefa.pdfIn PDF document text
    • https://www.verimevzabavu.cz/ckfinder/userfiles/files/54183925486.pdfIn PDF document text
    • http://gartenstadt-apotheke.com/userfiles/file/82444279721.pdfIn PDF document text
    • https://satesayap.com/contents/files/98784380814.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/1101407968.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/5359133909.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6ae022870---wixafewovidarulevebot.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/48305829298.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcc172d35a---lufebuwineruxubalopigose.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021090813445373499.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/15086711661.pdfIn PDF document text
    • http://lingeriedediva.com/UploadFile/file/2021091111555673499.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/92310491912.pdfIn PDF document text
    • http://nedvizhimost-v-sharm-el-sheikhe.ru/uploads/files/negagotazaxojuzini.pdfIn PDF document text
    • https://brs.jo/userfiles/files/demorasuwavafiwen.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/takesozanevuminaku.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/oabnm8umovd3vdm3f6ft5spcc1/48375142283.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=framed+apk+downloadPDF 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_off0000d6c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE0 10352 bytes
SHA-256: a337c6830da4dec80269d2ed24f0df20fac191cb276976c7dc52d184199ae9f5
font_02_sfnt_off0001062e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1062E 18272 bytes
SHA-256: 5fc1de888b8a0ebc81c277761e45e1eee3f4faa16adba94eb98981516c153e2c