Malicious PDF — malware analysis report

Static analysis result for SHA-256 e98e20c860e038c8…

MALICIOUS

PDF

88.0 KB Created: 2021-08-23 14:42:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 6822e01cdcd1019f406e7b3451d08930 SHA-1: 5dd9b56744b14ba9835e2463ed7af3faa64c7fd6 SHA-256: e98e20c860e038c80cefe1dafdcfb965267793aa7af089e3d87c77b044e1ff11
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, but the presence of numerous external links is the primary indicator of its attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/62731413387.pdf In PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/oesn48e5f4dq1ic4minqli8qd3/saweviniz.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/pirupulawagokedodezuza.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b154c54e807---zutonukepipejiwew.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/uefek8l36pv81ms4hfgahs2g75/29844895288.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/9300805451.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/bozipufowiligosezuvavibid.pdfIn PDF document text
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/181689069.pdfIn PDF document text
    • http://agriturismolionsfarm.it/userfiles/files/97622846549.pdfIn PDF document text
    • http://ypdtools.com/ckfinder/images_store/files/putugatupetafixes.pdfIn PDF document text
    • http://spearmanhsreunion.org/clients/e/e1/e1754705b4c076d7cd520c5e9e79ed07/File/rexubagadurepi.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f785284eb---57169542476.pdfIn PDF document text
    • http://notarbrazda.cz/userfiles/file/43752205931.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160742afe4f205---11675553550.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae75e4a849c---nusekuberexuveriwove.pdfIn PDF document text
    • http://adbuffalony.com/uploads/files/pigef.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/99514102090.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/42901706341.pdfIn PDF document text
    • https://global-brand.net/userfiles/files/55450234959.pdfIn PDF document text
    • http://locthanhroyal.com/upload/files/60186569932.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160743a4817190---tajolepupapuzapebewuka.pdfIn PDF document text
    • http://travelshops.pl/userfiles/file/lekipoxarakipewesodizivi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=7.2+to+fractionPDF link annotation
    • http://irodori.kir.jp/files/file/patubenug.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_off0000f45c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF45C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C6E 17452 bytes
SHA-256: ac5ed8a485bc41ff049221ecddd992484e6fa6473b517f61b3008bb8c7f0128c
font_02_sfnt_off00013a62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A62 10120 bytes
SHA-256: 51c93415f6400f2af53ea9107831475047ee36a139397a6a6c361152f1ff99bf