Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff483b84543c01c8…

MALICIOUS

PDF

83.2 KB Created: 2021-09-05 01:46:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 74a0b5c070a00aaec9e9ebc79eaa28f8 SHA-1: d5a63e1e50d283f3c8dd9b43a8127d54c49e67c8 SHA-256: ff483b84543c01c89b5dd74c06384f4ce6fe1ab4bd31dff3f7c6ea195b511291
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to other PDFs hosted on compromised or disposable domains. The primary purpose appears to be directing users to malicious content through a chain of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/hg4lbn7u3r2svj588ktsbkb9l6/neposabilowasevi.pdf In PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090096341b53---favonoxabolasoforejesu.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/150bf1d2tv26nbldo2edvoe8e7/94277809955.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/gagd3jhcg8lbansehjc6gj717g/52584680050.pdfIn PDF document text
    • https://quangcaomattroi.com/uploads/news_file/jopefel.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0c9d2916f5---40293047538.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/99837497997.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/29514599554.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/eoa9diev5mlflkvqgu33f06rs2/lilabetema.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/21195987380.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/61779613142.pdfIn PDF document text
    • http://ccapostolicchurch.org/clients/1/19/19d200bce63520a637954fb60b162b1a/File/17684188153.pdfIn PDF document text
    • https://coolingrealestate.com/your-home-cleaner/FCKuploads/file/niximaluziko.pdfIn PDF document text
    • https://ddms.tw/upload/ckfinder_temp/files/20210707202531.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/67462334834.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/h2mc16m4nogs5i0bss6qcled63/kovovupunutofumetozasew.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/nekogojazilimuwizezigogu.pdfIn PDF document text
    • https://adtw1.com/ckfinder/userfiles/files/74130984264.pdfIn PDF document text
    • http://azstorestudio.com/uploads/files/23397695752.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/14015779392.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/rinuwuxetefe.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/fv8b2lov7the8f24q0eekh7p1i/nuripizor.pdfIn PDF document text
    • http://globeksa.com/ckfinder/userfiles/files/64167755936.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/10082096040.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=tipos+de+aneurisma+abdominal+pdfPDF 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_off0000dfab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFAB 18516 bytes
SHA-256: 34ef44d191391a77a5497112a13d80b3b959f3689ee7fa037fff326d64ebc51b
font_01_sfnt_off00010ec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000126dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126DC 10764 bytes
SHA-256: 620e4310c1a1af90e759cc4a3f2c553dfcd0f239ad069560f38e80560f7c5782