Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdb78f0b24d8a688…

MALICIOUS

PDF

99.1 KB Created: 2021-07-01 00:06:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: b1ce49fcbf73b4ca8538acd896228e80 SHA-1: 17ffe976e6683f2accdec4f623c23ac65a91ce77 SHA-256: cdb78f0b24d8a6885a53485ccc8a2685f1dcd7010041349320a9d5bac11c60ae
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised WordPress sites, suggesting an attempt to host or distribute malicious content. The presence of numerous external URIs and link farm indicators points towards a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9784

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://dcoderesearch.com/uploads/51144630401.pdf In PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8da89a0043---zugotofigat.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/405d680f931573c43d244382914927bd/lofiwito.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a78274886e6---jekenilu.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a862566eb5c---28448623015.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/a9c3ba44ab254513deff23ac6696a74f/tiwejoziw.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/bebusuf.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606df34e76ab1---wimilaxaw.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/bimufetopotizufebaja.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f70352e5e---pafodelapaninok.pdfIn PDF document text
    • http://leguido.net/files/jezapafunapafofedez.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160aea5196177d---notajitugumixufazim.pdfIn PDF document text
    • http://boissee.fr/userfiles/file/fefazaxasij.pdfIn PDF document text
    • https://lienlacanien.com/img_pages/file/fuwenezinebebibuwejipi.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858eed8c10a---8924642358.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/4cbd5438074b7859e50a125d46b3b035/vewapatexik.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/belarad.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b66b00a466---fewefodudugusofagi.pdfIn PDF document text
    • https://aedwea.com/upload/foto/galunibana.pdfIn PDF document text
    • http://jar-ted.pl/file/dunalamev.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/5181c1904866d7014b5ac9298afd84d9/36324286253.pdfIn PDF document text
    • https://lentes123.com/aym_image/files/62136472128.pdfIn PDF document text
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/eofcntfnb1ddl2kvb8ojmc98l4/nusevat.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea2c8b79e0---99424154429.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/cc0f10cde7ebbc279bc00bce9b703226/gexadigujemowuxipifive.pdfIn PDF document text
    • http://womenshealthcarenp.com/clients/2/29/29a32d4da59f0b4eaa4573e1354aeabc/File/febejuruwitojuvazopilu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=blossoms+of+the+savannah+essay+questions+and+answersPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/zatugepom.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_off000120b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120B7 16808 bytes
SHA-256: ebe6e72fd7de596e700f2fcd5fa28f52d14ea8a96d32d1595856ea6e0b7da221
font_01_sfnt_off00014c56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C56 11184 bytes
SHA-256: b126a6217179cbd9782f3f8e1c5795a321cf70ba73e4a08fd80ba514d75cc6a1
font_02_sfnt_off00016639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16639 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1