Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6588c4593cf7adc…

MALICIOUS

PDF

74.5 KB Created: 2021-06-08 15:10:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3f5b6e1e016be2210a1e7d60bfe08623 SHA-1: 6744123ca3dc9d4bb6abb2f915ac02ce5ca54744 SHA-256: a6588c4593cf7adc7f0cb23ce612998860d4299751d6c91625f059f9dfe93c2a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains numerous links pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The embedded URLs and the nature of the links suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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 https://oniceh.ru/uplcv?utm_term=how+to+crack+amazon+manager+interview
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c090af14b---fowivewu.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ae61f10a6f9c7a9014cf5b8c03257da5/2635421788.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/a83f31b48936304c104dfd5ce5cb4392/48376929414.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16073fd7d814b5---xojidozoginizabasap.pdf
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/c4vh77mq0guoff961gc3df3vrk/pisiguwedifadikafo.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160945651a99b5---wogepozuziputan.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/43957989dc17c6518470f1f95d521dc8/58762728996.pdf
    • https://craftsmancuttingdies.com/wp-content/plugins/super-forms/uploads/php/files/cf0bc1e35a8ffb1009909ef2b7e97a00/8408037178.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607733e4cb54b---dusavuvoragosidodesenu.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/984384dd0c6f016809cda366a27f2a2c/94282276913.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5d5d857b2---gogugonafinixezaxofixav.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/79666617388.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985b2342e18---46340063355.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a1cfe787b17---mijar.pdf
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/9db652d26645939028f5e81cf9752223/78801744867.pdf
    • http://sicompk.com/survey/userfiles/files/24430003062.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6da.bin
141921e9f36ad255002807bb37c5b614532ba7b47e49e8af839e56030658f30b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6DA 5136 bytes
font_01_sfnt_off0000f865.bin
b8f903c1d80342592dfeec86c3e4b152c23c389cc87ae2f318d24a8c3efab325
pdf-font-stream PDF embedded font (sfnt) at offset 0xF865 10868 bytes