Malicious PDF — malware analysis report

Static analysis result for SHA-256 40616a50913784bd…

MALICIOUS

PDF

73.2 KB Created: 2021-09-27 12:51:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5b30d02642c1124aa7970bfca994032a SHA-1: 2789ac6076553b12cf3223d1b14cd179812f51d5 SHA-256: 40616a50913784bd297b9453f358688d2191c8956960427b53e58f5d1fba8ec4
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads. The presence of numerous unknown URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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 https://sangolongphuong.vn/longphuong/news/files/49889543965.pdf In PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/jiwewixubuno.pdfIn PDF document text
    • http://schokozentrale.de/idata/kubevoxagexozew.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/12857996012.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/bamunoxaxolir.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/titid.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee6da18056---31338750427.pdfIn PDF document text
    • http://biosystech.com/pdsFck/file/31023326026.pdfIn PDF document text
    • http://rafaelstore.ru/upload/files/95128298335.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16140d611d7387---kufilabonakulefixidi.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/pesudemonunagikij.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/bogonarizazi.pdfIn PDF document text
    • http://imobiliariaimperio.com/files/files/79894750678.pdfIn PDF document text
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/punude.pdfIn PDF document text
    • http://www.seminariomenorvalencia.com/admin/lib/ckfinder/userfiles/files/42709908826.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/jurepupilajuviraropun.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614bf858587a7---79999673272.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff0cbaec7f---26875246328.pdfIn PDF document text
    • http://dietmoiquangle.com/webroot/img/files/15705707385.pdfIn PDF document text
    • http://grotech.in/userfiles/file/galubesunedasutuligi.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/pekinedosumono.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387b3ab5c96---vanefitatujozujetotato.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/8219220802.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/e2eb91eae3e06654e382c3587d71a2d9/6489495823.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/70357187388.pdfIn PDF document text
    • https://onlinendttraining.net/files/67466444008.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/ximizizomutaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=omegle+video+calling+chat+online+freePDF 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_off0000ba5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA5A 16976 bytes
SHA-256: 57c168411a5c328bd3f7ea57e802cc67da7b81af5a050297226bb2b36fc37fa1
font_01_sfnt_off0000e609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE609 10848 bytes
SHA-256: d83112522a5c6dee2e9976691206761c3f6a0fd40e733e73104109020c945d5a
font_02_sfnt_off0000feaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1