Malicious PDF — malware analysis report

Static analysis result for SHA-256 838fba01e482122a…

MALICIOUS

PDF

90.9 KB Created: 2021-08-01 06:13:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c8aadec6679e928935f39273ed686a8 SHA-1: 0816f38ceff1dcb773067c0a2b8a252480adf119 SHA-256: 838fba01e482122a1797be4f378ee2ffdaaddb15058c56a72fbb2c0560c78e2c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS upload directories or disposable hosting, suggesting a link farm or phishing lure. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest the document's purpose is to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://daquin-ferriere.fr/userfiles/file/78539175671.pdf
    • https://atamergranit.com/userfiles/file/zesefenewawudurew.pdf
    • http://arnold-sitter.com/CKEdit/upload/files/dowivaxi.pdf
    • http://faurerom.com/userfiles/file/9454440961.pdf
    • https://fullgame.hu/uploads/files/15738202191.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3cf5cb794---gokegow.pdf
    • http://nessium.net/userfiles/file/refeg.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/ok29etehnqeupc0cekkqu6cq56/83489458852.pdf
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160820a229d0cd---65837811876.pdf
    • http://fairway.cc/images/blog//file/95123195150.pdf
    • http://tincorner.vn/uploads/files/95170860801.pdf
    • http://travelport.pl/userfiles//file/74313548848.pdf
    • http://dmkaudit.sk/101/upload/file/lezibezupuvekaso.pdf
    • https://keluargamimpi2.com/contents//files/fevon.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f37775bdd6c---sifomatamuvununuzevovop.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160febe58e9ed6---femegowapuwunuxasajigole.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b3cd6ef34---finiminuravi.pdf
    • http://the100voicesofgospel.de/fichiers/newsletter/file/rolilubitab.pdf
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/d03a54a560c03b19674218509b25e633/tepazon.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160f7566557ffb---61099476683.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=super+mario+world+2+yoshi%27s+island+emulator+online
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fca6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA6 16792 bytes
font_01_sfnt_off000114bd.bin
cc76c263625e86c0ffea5698362784052a9130002efd95ccaf4f74f4e540ca98
pdf-font-stream PDF embedded font (sfnt) at offset 0x114BD 11184 bytes
font_02_sfnt_off00012eda.bin
726874ecd9fecb8b5d876a88c69832103f48da10011e256fb444621a645d15f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EDA 17568 bytes