Malicious PDF — malware analysis report

Static analysis result for SHA-256 bdfb431cfcf41741…

MALICIOUS

PDF

70.8 KB Created: 2021-09-12 09:09:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 38511ec292f228f2086e948f67bfd2ce SHA-1: 823fc7e34c12d6be880e4fbed80d7e922dc43f17 SHA-256: bdfb431cfcf41741239a2de2a9936e6adf7b96e1e0ea8d53204da7dcf9be0192
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Several extracted URLs point to compromised CMS upload storage, suggesting a phishing or redirection attempt. The PDF's structure and embedded links are designed to lure users to external, potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135203354ad4---popexova.pdf In PDF document text
    • https://aordonez.com/images/contenidos/files/gogebewafaxisuram.pdfIn PDF document text
    • http://rhondachem.com/d/files/28599010652.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/98294381724.pdfIn PDF document text
    • http://apart1day.ru/file/tijigebivul.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/70685797134.pdfIn PDF document text
    • https://www.truckersplantparts.co.uk/ckfinder/userfiles/files/67640910444.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/45563457959.pdfIn PDF document text
    • https://mashura.co/userfiles/files/paxijovebejekomuxulami.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/ribukoxodinazopaxazage.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/jagikusotatekafefovonav.pdfIn PDF document text
    • http://gyn-ordi.at/myPix/file/90195284985.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/82885568633.pdfIn PDF document text
    • http://ranjitabiswas.com/userfiles/files/geloboxatilumuwefemotufuv.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5d8bec346---64897430817.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/d0e9958524b5d3c170deec5861f94e96/zewokabiwunogumus.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/22945816992.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/72777376034.pdfIn PDF document text
    • https://flardochform.se/userfiles/file/15721386685.pdfIn PDF document text
    • http://skazka76.ru/pic/userfile/57572967696.pdfIn PDF document text
    • http://gsemilia.it/userfiles/files/48014377424.pdfIn PDF document text
    • http://grandviewgroupresort.com/upload/files/96471694464.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/1679343532.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=18+news+live+malayalamPDF 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_off0000b0e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0E9 10380 bytes
SHA-256: 63020e45c48fd6a0b770443d898b82846dd34e7ceda34818dcd2104990fbab57
font_01_sfnt_off0000c86e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC86E 17324 bytes
SHA-256: 93d204dcb7e06ba3941123dc3da4a94a0df86e8d2f9d321b6132a66112925c56
font_02_sfnt_off0000f44e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1