Malicious PDF — malware analysis report

Static analysis result for SHA-256 277266aaea2031d3…

MALICIOUS

PDF

80.6 KB Created: 2021-09-03 19:45:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: dd80e3a8ca336cda2e96ed9c6c5daec3 SHA-1: dfab076596d8647c554a7dbc20ef3285386497a2 SHA-256: 277266aaea2031d3d7dac0944e1c1bb8b0c9b1217c6aefcafe15a721c31c0859
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, identified by heuristics like PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ccea248d1d---82954806664.pdf In PDF document text
    • http://dfh-consulting.com/userfiles/file/82851780720.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16070b7f8c1490---53619053588.pdfIn PDF document text
    • http://nawooelcs.com/upload/userfiles/2021/08/files/210825154929.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/95273832603.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3d5654f0b---82517791718.pdfIn PDF document text
    • http://kukdae.com/files/fckeditor/file/97054793377.pdfIn PDF document text
    • http://kindergartenhelden.at/upload/file/14309063172.pdfIn PDF document text
    • http://hesexpo.com/img/editor/image/file/bazejupep.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/54e3c1e032e2d47302faaf17dc9dc78f/fibobuvesazenuzogefoda.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/jupegoxade.pdfIn PDF document text
    • http://frickcontrols.com/uploads/files/76228634591.pdfIn PDF document text
    • http://rracc.com/file_media/file_image/file/wemisu.pdfIn PDF document text
    • http://imssp.by/data/images/fxeditor/file/lorixigepo.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c61eb31076a---luralixudutogex.pdfIn PDF document text
    • http://0-50.ru/userfiles/file/33372321369.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c0757e74ada---44631404848.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c2033a853---58911692161.pdfIn PDF document text
    • https://gwynharmon.com/home/gwyn/public_html/ckfinder/userfiles/files/golumomoluviditoxe.pdfIn PDF document text
    • http://dsraxys.com/uploads/fazoxoxukesorapitegu.pdfIn PDF document text
    • http://feach.ie/images/uploads/file/mawabup.pdfIn PDF document text
    • http://enewind.com/pliki/file/pinezuperadusojife.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081e43125ed6---xuzobupudotodorufadozan.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=polyspace+bug+finder+pdfPDF 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_off0000d4bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4BF 17892 bytes
SHA-256: b7b1a14548e51764a88a3ef3dde334c963e8aed0239d7f0aeb39a72395f720b9
font_01_sfnt_off00010371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10371 11052 bytes
SHA-256: 868caa11089e54a9b9fa73fc38175f080fa617e42995bf1bbdf89de834bf6dcf
font_02_sfnt_off00011ce9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1