Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1e2a1e76cbdd488…

MALICIOUS

PDF

87.0 KB Created: 2021-09-15 11:47:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 88e83408b74808f0e0360405329129f9 SHA-1: 29c5fefa8e6ad50eb7e7e088a71e5ea08389540e SHA-256: e1e2a1e76cbdd4885d7fa1e9d4d31321ed3b718a6d922d5616163b7da704a11e
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to domains associated with link farms or compromised CMS upload storage. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for link distribution, suggesting an attempt to manipulate search engine rankings or direct users to malicious content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://nj-rshb.com/v15/Upload/file/2021911717469715.pdf In PDF document text
    • http://happy-land.hu/editor_up/berijib.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/zozazexazuresemetanurifi.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16131c516a9e2a---xisavaro.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/24849490621.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16133034e581ca---tefunasare.pdfIn PDF document text
    • http://umrllc.com/userfiles/files/97172516243.pdfIn PDF document text
    • http://kechengchem.com/upload/files/vunure.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/22364081237.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/78392149896.pdfIn PDF document text
    • https://masukpt2.com/contents/files/zibapagevukigekew.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/498a31893edeaa76fa5ada9252e9db6a/20535159301.pdfIn PDF document text
    • http://lpxs168.com/filespath/files/20210910151529.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161364f51c34a1---5548308751.pdfIn PDF document text
    • https://paidionresearch.com/userfiles/files/58569378063.pdfIn PDF document text
    • https://saikekanglun.com/filespath/files/20210910105134.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413bfc83526---2103493856.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/rigowopijexudujis.pdfIn PDF document text
    • http://iucecb.com/files/file/nimimamijebisoxig.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/gowemogod.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/lotijukevuwejaf.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613757623fba2---gavilo.pdfIn PDF document text
    • http://pribatu.lamilagrosaimport.com/images/files/rosirixivekujutewowot.pdfIn PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/jisonepujudujisif.pdfIn PDF document text
    • https://mrdak.cc/uploadfile/files/nedexawoxu.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614162058da89---90975926677.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/3faf6f3cb9edc012d5e3bd503a7c512f/sivexaraxut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=everblaze+read+online+freePDF 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_off0000ef84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF84 18084 bytes
SHA-256: e78d8201ce962b25278e0dd2493918ef1f0a48f4dd391dc56c7dfec53d3defe9
font_01_sfnt_off00011e55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E55 10328 bytes
SHA-256: e5afeed50c457b9fc62e0008c4a1a789090bf45a1c32b038ce403ee18e4b4285
font_02_sfnt_off000135b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1