Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff333bd70faaa2e4…

MALICIOUS

PDF

94.7 KB Created: 2021-08-13 11:36:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 737d7f9a6d1a26422d1cbf983d408194 SHA-1: 307b2f35dd1eeabc9311d40a7d1ea04127e0448a SHA-256: ff333bd70faaa2e46488abd5aaf98f5eb685d537022d96a09f9b8c4f7023dc8a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript to facilitate redirects or exploit vulnerabilities, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://matstravel.ru/userfiles/file/43217834887.pdf In PDF document text
    • http://cissi.it/userfiles/files/71790316022.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f12c236cee---polabex.pdfIn PDF document text
    • https://phr4u.com/files/sipixaberifaramub.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/7df88a5b48e9cc833518b6d7fcd24181/lazaf.pdfIn PDF document text
    • http://juentai.com/userfiles/files/demoteromowekobelomasadud.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/45748bfcc548bac21150f76abe0204c0/52310090905.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/9db6aff512a03a2718bcb272d59dc199/gutuwifawusek.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/65520849213.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/lezubulobas.pdfIn PDF document text
    • http://k-souz.com/userfiles/file/68403145113.pdfIn PDF document text
    • http://tomdythai.com/userfiles/files/24930667918.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/6170289007.pdfIn PDF document text
    • https://magatek.com/documents/file/14243565238.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a57f8761ca5---tugiwugisiz.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/samepudeges.pdfIn PDF document text
    • https://megalightgroup.lv/uploads/files/21702509807.pdfIn PDF document text
    • http://wjcopy.com/upload/files/xulopefubaforiwimof.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/201a6a4ffd498384b79d425e8d803c77/givofugoturofozamur.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/23588067206.pdfIn PDF document text
    • http://studiofapas.it/userfiles/files/40263490281.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=is+acupuncture+used+to+treat+depressionPDF 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_off00010f28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F28 10512 bytes
SHA-256: 80c615348a0e6781f6d23f88b07165ac0137c5e702c1c1ea05bf8d440992bdf4
font_01_sfnt_off0001272f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1272F 17140 bytes
SHA-256: 8d00b91d6f102262b4a871b1e7ac4289deac487ad4de702ee759af6a4522de22
font_02_sfnt_off00015394.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15394 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1