Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bf28de8f5640d77…

MALICIOUS

PDF

88.2 KB Created: 2021-07-02 05:44:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e6cff65d4d7abbbdb53157405511c076 SHA-1: 3a901be69b6c128dfc1fbfa5ccab45e1b3f7cb2e SHA-256: 8bf28de8f5640d776b03946e2b672f86fef9ba05c90f2530faa72a22163e1943
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution intent. It functions as a link farm, directing users to multiple compromised WordPress upload directories and disposable hosting sites. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content, likely for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/9e16770ba26bed82d5000b0bcea973b3/37558065307.pdf In PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607495525b825---98806373374.pdfIn PDF document text
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/69cf27af5e5ea024b9d12fd7bbe43d17/24886098939.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160867a594f7be---29212658893.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/561734b82cfc4c3b4ce134ffb6c70a80/49457644064.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/28601088001.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/e96ac88f87c60d3362d1fb7862d807df/dedusuduliku.pdfIn PDF document text
    • http://clinicaveterinariailmarzocco.it/userfiles/files/jodatafusaxegameku.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/6945667220.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/30dad2cf52a2b27e19a903f5f5a18fca/pamabidodiboxodim.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1608e49efbd276---53568696417.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/40d4b6a0ea0a346f62e68c92acfb2d05/42222535920.pdfIn PDF document text
    • http://3mfa.com/images/editor/files/lamomuzuvakesafefosen.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b219a914cb1---wepotanolegaketegov.pdfIn PDF document text
    • http://vce34.ru/attachments/file/tunazalas.pdfIn PDF document text
    • http://nousgarage.com/userfiles/file/femibudu.pdfIn PDF document text
    • http://euro520.net/userfiles/file/16245036381742567142.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/4d4eb918ec8aff09fff9878af9abca1e/51593641412.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/3gnmetrr9e8t2its17inimu8e0/78186506633.pdfIn PDF document text
    • https://bataretak.com/img/files/file/bizukiwukofalijebunigat.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/82478917485.pdfIn PDF document text
    • http://grapevinewinerytrail.com/clients/876125/File/femumowubosugopelopason.pdfIn PDF document text
    • http://cassotech.nl/site/data/ws/files/vixaxizalebenojitin.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/zodamifoxexedini.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=football+quiz+questions+and+answers+with+optionsPDF 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_off0000f57a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57A 11000 bytes
SHA-256: 6a88a1e873367e41edd7f99fd0ce05c73ddeb97fcfbf866c74abf41aad2952e2
font_01_sfnt_off00010ea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA5 17120 bytes
SHA-256: 1579dc86bd7551032d9ce8f3fc3bc0ff6e78af31ad988fdb9aec180867db9c84
font_02_sfnt_off00013b20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1