Malicious PDF — malware analysis report

Static analysis result for SHA-256 2131cb259fbfde5b…

MALICIOUS

PDF

81.5 KB Created: 2021-09-13 12:37:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2b4a9b7ebf13851a32541dbc6dc15b02 SHA-1: 845d08f95255261710c75f1acea8c2513157f5a9 SHA-256: 2131cb259fbfde5ba6172555f55113856aed0766ccf3f0a651b3142bd99cfe97
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting a link farm or phishing lure. The presence of embedded URLs and the overall structure point towards an attempt to redirect users to malicious content or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb2321d6a8---rurozelekepuxojavo.pdf In PDF document text
    • https://saptabangunmanunggal.com/indomobils/upload/file/fosenexumubideput.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/falitab.pdfIn PDF document text
    • http://magdrywall.com/project-new/christianbook/upload_images/file/30447609501.pdfIn PDF document text
    • http://land89.com/ckupload/files/piwebubufefivigevopi.pdfIn PDF document text
    • http://midesignvn.com/uploads/files/waxoba.pdfIn PDF document text
    • http://htwy.com/upload/file/16027515529.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/pefufifipuselabudox.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/41509043340.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/55660717648.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/janilafopexeberuvaz.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/sogijusofovomefupas.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1a6b7ddce---getefizukomiwuleridetune.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/df650d0d747cecf3d7e4ae70ab2b6238/32369186431.pdfIn PDF document text
    • http://ned.ru/uploads/files/53553062007.pdfIn PDF document text
    • https://detectagsafety.com/ckfinder/userfiles/files/15031104159.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/taditepafuguxogagoba.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/bizev.pdfIn PDF document text
    • https://linardi.ru/files/file/zifosuw.pdfIn PDF document text
    • http://auto4-spb.ru/public/images/ckfinder/files/88948312633.pdfIn PDF document text
    • http://bamor.org/userfiles/file/75245910603.pdfIn PDF document text
    • http://resumesfromabove.com/userfiles/file/6293295614.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/motosumonuti.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210912055947.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=android+proxy+authenticationPDF 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_off0000d816.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD816 18084 bytes
SHA-256: 0a035dba2977fee09101c4f6486c1c2c121ba8f917a969bffdfea5ee52a61d9c
font_01_sfnt_off0001076e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1076E 10692 bytes
SHA-256: 762b0a4d929431fc2950475f81ebe9f48df5b5b2f45d4a893a57298bd29dc16d
font_02_sfnt_off00011fef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1