Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0e39a7e57022ce4…

MALICIOUS

PDF

104.0 KB Created: 2021-09-08 08:56:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 07823c1ce58b5dc41ca8cb8eb27a590a SHA-1: 83d5ff5df6355576cc3c7a5a82901f0aa706cb1d SHA-256: b0e39a7e57022ce434e797c8726a033da637a40d92f09b183ccb149793797678
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious or phishing sites, likely as part of a broader phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://tatishev.ru/admin/ckfinder/userfiles/files/36198728366.pdf In PDF document text
    • http://old.smartplus.pl/ckfinder/userfiles/files/67676102317.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/99835129977.pdfIn PDF document text
    • https://laznia-radom.pl/userfiles/file/dipomujoler.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160937f921c706---18711159258.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16074927dd9db3---63759563554.pdfIn PDF document text
    • http://thanhtindesign.vn/uploads/image/files/kigipixupa.pdfIn PDF document text
    • https://mysmartedu.com/uploadimages/files/97191219455.pdfIn PDF document text
    • https://mediaget.ru/userfiles/files/muxizov.pdfIn PDF document text
    • http://akbarestate.com/survey/userfiles/files/9840347107.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/35869470322.pdfIn PDF document text
    • https://projetovm.com/uploads/files/botepafulapituxuduromit.pdfIn PDF document text
    • https://drlanda.hu/user/file/83529908206.pdfIn PDF document text
    • http://dr-temt.ru/images/file/92692629369.pdfIn PDF document text
    • http://www.olivier-frey.ch/user/web/file/kusokodasowapedilo.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/mepetogu.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c64263dde37---suwinifexokozulug.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/714b8e4196e412bd4247d2df0ef937aa/fasabiguwuxibararosiripu.pdfIn PDF document text
    • http://thedreaminitiative.org/Content/Admin/uploads/files/10894189884.pdfIn PDF document text
    • http://citadelcaralarms.com/userfiles/file/72452492076.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/7ce4d7fd1130952261925a4f2dfc8dca/sepinirixakosota.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210829_33F0AB42F7D97790.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/53i5c57ptk25bu9h6454o0e44h/5822666279.pdfIn PDF document text
    • http://jaatkinson.com/userimages/59014956036.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=refutando+o+calvinismo+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_off00012e83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E83 10892 bytes
SHA-256: 2e7d2e348421aa0cd401ec7d294ec4e3cb5e2984b9998eaf1df5cb0240589ef2
font_01_sfnt_off000147ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147BA 19332 bytes
SHA-256: af83050154a91897abd444c62aa8cee5c23f15eb9b91884032817075f76a7eed
font_02_sfnt_off000179c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x179C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1