Malicious PDF — malware analysis report

Static analysis result for SHA-256 73fcfd1b46642516…

MALICIOUS

PDF

79.7 KB Created: 2021-09-20 10:43:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7015eaf3ddbca8100e6085d50f50e3dc SHA-1: 52480cfbe211d55ec3cdfea96b86af851f4d3093 SHA-256: 73fcfd1b4664251671d67d5473d240b4a657198a22444dfdfb14426e6998a86b
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to obscure the final destination. The presence of numerous unknown URLs further supports a phishing or redirection-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://chsins.tw/uploads/files/202109192228551673.pdf In PDF document text
    • https://tybistanbul.org/resimler/files/5718923696.pdfIn PDF document text
    • http://2222.netsociality.com/upload/files/rabukezi.pdfIn PDF document text
    • https://netcsemege.hu/ckfinder/userfiles/files/voxasakowul.pdfIn PDF document text
    • http://www.valaisconsulting.ch/file/35684994725.pdfIn PDF document text
    • http://www.polni.si/Images/files/wefojenerifufedugo.pdfIn PDF document text
    • http://japhina.com/upload/file/gusifejar.pdfIn PDF document text
    • https://egca.fr/userfiles/file/semav.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/58934758954.pdfIn PDF document text
    • http://phayaotechno.com/UserFiles/File/17869112423.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/6f104ad961fb9371006af118846097e9/feletota.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/373fb637b9249cb2ef22cdf4b7911839/90163399037.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/mirosenowufidezo.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2ac4d2d71---97219847252.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/sasazem.pdfIn PDF document text
    • http://boxshop.mn/userfiles/files/fonejitoruj.pdfIn PDF document text
    • http://lamorenj.com/userfiles/file/13430616357.pdfIn PDF document text
    • https://getadoc.in/ckfinder/userfiles/files/69212539328.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/39422059907.pdfIn PDF document text
    • http://kleinschadenexperte.de/userfiles/file/45180032174.pdfIn PDF document text
    • https://zhbiotech.com/CKEdit/upload/files/wasonurorepumozume.pdfIn PDF document text
    • http://gryfarmerskie.pl/pliki_wyswig/files/99286472867.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/11433846051.pdfIn PDF document text
    • http://vinhomeshaiphong.net/app/webroot/img/files/xawigisuwopuwewepafezagaj.pdfIn PDF document text
    • https://cyc-catering.pe/disac/userfiles/file/mixogopiwuvusumoxibetagep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=the+legend+of+zelda+ocarina+of+time+nintendo+64+romPDF 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_off0000d17a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD17A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e991.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE991 11024 bytes
SHA-256: f6ed0f21be505402b58e6110d6a3b65879e474e7a29ef1ebb19ae06e5f586960
font_02_sfnt_off000102e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102E1 17164 bytes
SHA-256: b31244f9c13569c1ebbd753346416db76437652dc2ac718685f299182a45d877