Malicious PDF — malware analysis report

Static analysis result for SHA-256 10c3bbcda74b96c4…

MALICIOUS

PDF

75.7 KB Created: 2021-09-02 15:36:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b81a6f92c3f5d8163385e22898f410d9 SHA-1: ae37be48d1a33b76260b1efa23493bfb356a47c8 SHA-256: 10c3bbcda74b96c4fd979026e97ae21a9094a8fdd0006c45ba699c598ed130b2
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress upload directories. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. The presence of multiple links on potentially compromised or disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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 http://balone.net/_upload/file///9344388741.pdf In PDF document text
    • http://jhdjt.com/images/upload/File/87346249060.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e9d6989f5---xurefagupojozepubozem.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/4d9ee28166e512bc1ece46aa52693f13/59686220917.pdfIn PDF document text
    • http://7tec.ru/userfiles/files/75756633145.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/vetirelopasipejutupiv.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/2e4bbc5f3e591b4a50080e5b9257e98d/36493398881.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/bupujazoruduvolakasazezim.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/asq3rpar0maih8ctkr3r00dll5/ziwedakabasuponovoruro.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/jp7ikt7hvmp74hg7q6gq0oug2d/wiginabopexerazof.pdfIn PDF document text
    • https://go2germany.ru/files/file/voxikewatetovapikaji.pdfIn PDF document text
    • http://www.look4job.gr/images/_user_na/file/malisidupive.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d8d482a2c29---tonuwumarewolo.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/2v8aenvu2c2lpgid20q0lfq1ba/14841923710.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/58001020033.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3a8523dc0---42345296339.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/damepowezumavinefimomimi.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/78707379963.pdfIn PDF document text
    • http://thebellingerfamily.com/clients/0/05/05034faaa501c69409a7459485cba135/File/xikezakofotipuligivolot.pdfIn PDF document text
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/61873942413.pdfIn PDF document text
    • http://gasthaus-steinkirchen.de/img/editor/file/dadowixerosesikudixeluge.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/4eb2df7952fc4066a4f50aa894fa4a17/30203337218.pdfIn PDF document text
    • http://7tec.ru/userfiles/files/duzoru.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/139092nskqm3v1bea3lnn4gc85/dawoluzezuvuse.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1816c1bd62---91006009181.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/21027377254.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4012412919---dewinaganadubifavigosa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=behringer+virtualizer+pro+2024+manualPDF 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_off0000c3fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC0D 16796 bytes
SHA-256: 769c0422150d61e460086e41e4cc019a6670aac8455e0ab8386f00c7a42415ad
font_02_sfnt_off00010747.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10747 11128 bytes
SHA-256: 83235e1b03e0f7af93f13da0ab627f7e30faf9b923e770c9e9c388bd2a06aeb9