Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4f3763a5e77518f…

MALICIOUS

PDF

79.0 KB Created: 2021-09-16 02:52:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8775bbbdb500722671b2c0512861d0ff SHA-1: d3e080606a07c5d710399c84163b102c6bfdec6d SHA-256: a4f3763a5e77518fa85aa98c646e52897f26ef051e3c74984e6ffa19bd9a8de2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by multiple heuristics and a machine learning classifier. It contains numerous embedded URLs pointing to external domains, many of which are associated with link farms or disposable hosting, suggesting an intent to redirect users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior. While no scripts were explicitly extracted, the nature of the embedded URLs and the overall detection pattern strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • 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.
  • 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://garglob.ru/uplcv?utm_term=types+of+charts+are PDF link annotation
    • http://zamgph.com/uploads/file/020836397476.pdfIn PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/60597623544.pdfIn PDF document text
    • http://ilink.pl/userfiles/file/xafezudowuvumemapum.pdfIn PDF document text
    • http://e-menu.hu/editor_up/koladogamepugiviwakapa.pdfIn PDF document text
    • https://alshuka.ps/ckfinder/userfiles/files/pozasofilimutaxafi.pdfIn PDF document text
    • http://paulgraphics.paulsfashion.in/files/88166910251.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/161361edd1a783---fojasejiwipowomirawazo.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/sudapamuzovasarezimufa.pdfIn PDF document text
    • https://indiantiffin4me.com/nbloom/fckuploads/file/8375835140.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/jevowupilokumitot.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/62965720330.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/161408d12457ee---54079815842.pdfIn PDF document text
    • http://teenmag.cz/userfiles/file/84978616926.pdfIn PDF document text
    • https://stiff.pl/ckfinder/userfiles/files/965690835.pdfIn PDF document text
    • http://mlsy.cz/images/file/files/wuloroligesuporowiz.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/17519084387.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/2245839966.pdfIn PDF document text
    • http://www.photonics-science.com/ckfinder/userfiles/files/72601590936.pdfIn PDF document text
    • http://ettorebelfioreliutaio.it/userfiles/files/83527786399.pdfIn PDF document text
    • https://accounting789.com/ThImg/file/8728276580.pdfIn PDF document text
    • http://vagtteam.com/userfiles/Files/56840136219.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/jibarobabutope.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_off0000d3d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3D4 10412 bytes
SHA-256: f0424b0258bf09d65ca3bd1c09c66eb34eddd0a0533ec78a35d5e79fab79618e
font_01_sfnt_off0000ebab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BD 16596 bytes
SHA-256: 7a89fca9bd196cbd5392a1ea1fa13df8c0904c4468920f572a50b749de6ce4b4