Malicious PDF — malware analysis report

Static analysis result for SHA-256 f94af8595ec19158…

MALICIOUS

PDF

82.5 KB Created: 2021-06-28 19:36:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: e7f19a8e57dbc72d7afeb1c5d644ab50 SHA-1: d9fb7ab1e4f728db9f8efee12713058ff0099ec4 SHA-256: f94af8595ec19158bf42db587d6961f2fdba87667d0ea30ea5839060e1e17dcf
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous embedded URLs point to compromised websites and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true purpose but reinforcing the malicious nature.

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://smidgel.ru/uplcv?utm_term=price+of+deed+of+sale PDF link annotation
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/160735d3d65b8a---52845685063.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abda6349019---bapoku.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/46096405450.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/ohgcotsc13cv5nv5t9clf44d0v/23342029731.pdfIn PDF document text
    • https://victorybear-info.com/userfiles/files/vefalesasimawafij.pdfIn PDF document text
    • http://anbao.vn/uploads/userfiles/file/bolawapo.pdfIn PDF document text
    • http://xn--l3cbpp3gh4a5g5c.com/userfiles/files/72204130632.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/77421708031.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/0a28b70e99d3f92ba4b77fc9c68feae6/67390046252.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/nh2i1v9hsh1ip4100qd31f2ur1/5046065880.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a27095b4e7e---lobonumigakunalutawesumil.pdfIn PDF document text
    • http://etcad.net/np/upfile/file/zimaja.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/vabomonili.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607559a969e93---47308760622.pdfIn PDF document text
    • http://ingenermarket.ru/userfiles/99477118661.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/3tv5g3n99cr3cggd7c6hktekd8/pupakarolipufazirusinedes.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/2e0760eeddddcc8862833fdfa6946897/poxizaxogutekasevew.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c36207438a6---9751702633.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/92488423589.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/trfl45rv11d1oep3hmt8g8lvh9/23502639852.pdfIn PDF document text
    • https://anakmeong.com/contents//files/5887444871.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/v54lceo4qn6m9jclo1fgtek4bu/lusitelubirigajabu.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a615c6cb768---kimemaxufo.pdfIn PDF document text
    • http://rld-carbon.ru/file/93653962402.pdfIn PDF document text
    • 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_off0000e3e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fbff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBFF 10268 bytes
SHA-256: 3a244110caee57d4faf12e41fcfc25e5db7c4371c69d12ee2fdd6789bbff376f
font_02_sfnt_off0001132b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1132B 16168 bytes
SHA-256: a042ebf045b20646aa53f7a92df89ccc535e3df2ddf68cd96a4ccfcbc49a8081