Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a92e72550719880…

MALICIOUS

PDF

82.5 KB Created: 2021-09-14 12:24:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: f49bfd410bd626f0e1fc0404cbaf317d SHA-1: 442ca82dd2548df321995622babe0bdaa18421d6 SHA-256: 7a92e72550719880b432b819083c5feb65e01fb259312b3446532f7b25a6d384
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. The presence of numerous unknown URLs suggests an attempt to direct users to potentially malicious sites for further exploitation or phishing. While no scripts were explicitly extracted, the nature of the PDF and its numerous outbound links strongly suggest a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://robwalker.net/fckupload/file/43910369470.pdf In PDF document text
    • http://chafewyuok.handysociality.com/upload/files/mikel.pdfIn PDF document text
    • http://christ-china.com/filespath/files/20210907025755.pdfIn PDF document text
    • http://www.tecnologycenter.com/admin/uploaded/fck/file/dutotirigoto.pdfIn PDF document text
    • http://twtime.com/uploads/files/202109012334359410.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/jironogubifila.pdfIn PDF document text
    • http://dreamsurgerycn.com/ckupload/files/83883120945.pdfIn PDF document text
    • https://hsse.cl/files/50213184055.pdfIn PDF document text
    • http://irinaburmistrova.ru/files/75405321322.pdfIn PDF document text
    • http://racecross.com/upload/edito_fckeditor/file/33034063645.pdfIn PDF document text
    • https://self-storage.sg/images/uploadedimages/file/kowadipopikoniki.pdfIn PDF document text
    • https://nexapos.com/upload/files/fozarurowoxurijevezi.pdfIn PDF document text
    • https://schachverein-marchhoefe.ch/fcsr/news/upload/file/tegupiteg.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/28652687555.pdfIn PDF document text
    • https://bela.geekers.tw/upload/file_folder/file/81710817736.pdfIn PDF document text
    • http://www.saletime.gr/admin/fckfiles/file/petopewafujidokomifu.pdfIn PDF document text
    • http://bbmpva.nl/fckassets/file/fikufa.pdfIn PDF document text
    • http://hflchw.com/upload/file/damuvapaxoro.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/biwawibawufejaredu.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/daxujavag.pdfIn PDF document text
    • http://woodbridgeabw.com/uploads/files/47799662949.pdfIn PDF document text
    • http://nontaromclinic.com/ckfinder/userfiles/files/27311424788.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/zubesariwigomel.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/sebamare.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=is+spinach+good+for+stomach+ulcersPDF 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_off0000dd30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD30 17508 bytes
SHA-256: e332673f78973b22f65576c58df534036ca386c99007d0acb08ecd984b759719
font_01_sfnt_off00010a97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A97 11120 bytes
SHA-256: 3a4a5d958b21871db57074dcc39b23fe8c02170de47ddbff3206b9dcca62b602
font_02_sfnt_off00012425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12425 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1