Malicious PDF — malware analysis report

Static analysis result for SHA-256 11ac808d5e6c7bed…

MALICIOUS

PDF

83.2 KB Created: 2021-08-06 08:56:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dd6e46887f836547d05ab445d6422932 SHA-1: 25a6cac170120f8bbe951d8ab715aa65ac80dd92 SHA-256: 11ac808d5e6c7bed82b58acdefd66a1c459f14e9169f553ddfb118a8944a8a6c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs that form a link farm, pointing to compromised WordPress sites and other domains, likely intended to redirect users to malicious content. No scripts were extracted, but the presence of a link farm strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://citra.cl/userfiles/file/55500488084.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/fp00pl6oesdfu0fge3h8oh0ij2/sasuwagatebigurasuwef.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bd00ce5502---terizusigikeririgudor.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078ff4fe8bfe---kujame.pdf
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/be72e12bc3ffdb4f8003f5ef5bac63b9/vosupokapu.pdf
    • http://sanmorales.es/userfiles/files/baruwuxe.pdf
    • https://atamergranit.com/userfiles/file/zirizamab.pdf
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/lepabi.pdf
    • http://appletechsolutions.com/userfiles/file/pakobofosijabetakuguk.pdf
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16205896416532.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfdd884d72b---31214089761.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/hk15rvk8gj4l7uaad7egfblb4f/pumakob.pdf
    • https://urbanlivin.lu/userfiles/files/52719119551.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/e8288b1fa447932f12a0c3c4d06c4393/14492312143.pdf
    • https://codecs.roimages/file/17134859973.pdf
    • http://wittlich-luexem.de/userfiles/file/14334834375.pdf
    • https://yarpaket.ru/userfiles/file/molafepejazafo.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160edb883b9ad9---bawanetarisavitajalupori.pdf
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/afd4ee52d2916bc06d16e96f8ce11c91/2110585478.pdf
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d3b1989fb---jolife.pdf
    • http://www.bufolari.com/public/immagini/file/gijimajoparumabaxonitumon.pdf
    • https://asthasupermarket.com/userfiles/file/jubumakasurulab.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=regra+de+sinais+-+adi%C3%A7%C3%A3o+subtra%C3%A7%C3%A3o+multiplica%C3%A7%C3%A3o+e+divis%C3%A3o
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d793.bin
edd4f3bb2d6ef4de5f600655a0c40c5cfa4a96974244b8a0200b7529d027e879
pdf-font-stream PDF embedded font (sfnt) at offset 0xD793 11704 bytes
font_01_sfnt_off0000f262.bin
8ab6e75aee12275722a42b427fa383dc0fe4ca1024c2ed22c465a548b222d156
pdf-font-stream PDF embedded font (sfnt) at offset 0xF262 19588 bytes
font_02_sfnt_off000122a9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122A9 16792 bytes