Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0ee83c92ee07bfa…

MALICIOUS

PDF

88.3 KB Created: 2021-09-10 13:33:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0adb13108f71b93045302232abf60236 SHA-1: 9587c7d0bcc3c4de7bbf684f3a5d399c294fbdbd SHA-256: b0ee83c92ee07bfa6f75c8ed84d52c87981e2a19e3ca69f4775fa23f52bcf1c6
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 many URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or redirection scheme. The document body was unreadable, but the presence of numerous external links strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://infrabud.eu/fckpliki/file/rupowuwugakovoxe.pdf In PDF document text
    • https://blnk.eu/userfiles/files/tukofalu.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd592398cf---rutap.pdfIn PDF document text
    • http://bestofbeer.ru/ckfinder/userfiles/files/xifawibufedolupevil.pdfIn PDF document text
    • https://wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/77909493643.pdfIn PDF document text
    • http://lisaarkinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/77875225647.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/ca7c31cd6440216c3f00d44b4d70320f/mefew.pdfIn PDF document text
    • https://asi-filter.pl/files/file/tefopuxalodexenila.pdfIn PDF document text
    • https://jeevandeepspecialcare.com/ckeditor/ckfinder/userfiles/files/78208052330.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16139a1f0e6e6b---36912637232.pdfIn PDF document text
    • http://eros-arena.name/eros/userfiles/file/vumexaduwaxix.pdfIn PDF document text
    • http://educaholistica.com/resources/img/imagesck/files/37438542202.pdfIn PDF document text
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/waximufeza.pdfIn PDF document text
    • https://ajambary.com/userfiles/file/75211033230.pdfIn PDF document text
    • http://www.jasfec.com/imgs/uploads/18000838496.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/tetekapapakeramuwowef.pdfIn PDF document text
    • http://security-m.jp/tool/images/file/15123996665.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/45342987133.pdfIn PDF document text
    • https://congnghiepxd204.vn/upload/files/bezegapuzevuralumew.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ecd22c48c---dasarubidukevixafap.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16133823155d66---pirajugepofapagibovet.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/23060569896.pdfIn PDF document text
    • https://giriconsultancy.com/content_files/files/pilepudubipawupipizejepud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=google+sites+newPDF 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_off0000f928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF928 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001113a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1113A 17024 bytes
SHA-256: aac0753e8fa4718ce2617ff46eab0796576c1ce37844f3c66b0b644fd001f114
font_02_sfnt_off00013d58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D58 10148 bytes
SHA-256: 9051f279b205196bd208134122f9160931be2fa7d7c282836ddca000c56f0d8b