Malicious PDF — malware analysis report

Static analysis result for SHA-256 844d99f57a29ae59…

MALICIOUS

PDF

74.6 KB Created: 2021-09-03 18:56:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e74b87229de38050c4c4c1522f417dd0 SHA-1: 874b558969ab76ce31112ee216b21eb14ca3791a SHA-256: 844d99f57a29ae59bdd2f979c7e80ec613c308cb777735e76bfc89c321f9c2d3
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple websites, several of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or phishing sites. No scripts were extracted, but the structure and URL targets are indicative of a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe4dcd996f---ripofi.pdf
    • http://pkynfe.net/userfiles/file/74566877550.pdf
    • https://akapacha.com/userfiles/file/79703219232.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/8vjtimh3fvqdlbdr4p0cjmvpm0/74068881492.pdf
    • http://zussobrance.sk/grafika/dokumenty/notesab.pdf
    • https://geneticapanama.com/userfiles/file/26332025621.pdf
    • http://lammermoor.net/imagenes/file/50857930590.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/a3b002bd264d681f129f51d8c8602a3b/50807614056.pdf
    • http://atlonnuri.org/UpLoadImage/editer/files/lerolitof.pdf
    • http://zulassungsservice4you.de/bilder/file/92305872291.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160790e26a0313---jitoguzetelirif.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e7083f20970---36797650894.pdf
    • http://karthikeyanjayaram.com/userfiles/file/sawoporerupatikogex.pdf
    • https://cuisinescartier.ca/upload/editor/file/wosegijetomexenuxeluva.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/161122e7e7df78---nijadi.pdf
    • http://tanriovermensucat.com/uploads/genel/files/82868556453.pdf
    • http://tylincms.com/userfiles/files/memawavizufimidimogo.pdf
    • http://www.amanuttarakhand.org/ckfinder/userfiles/files/50902275649.pdf
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/kikaj0jdnvru2vpsn22o6i4ks5/80635575624.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/m22v9ceri72piv2bvt1ggsamm3/gimixexelukedat.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16108674c44d21---fivupabebora.pdf
    • http://ltmetal.com/userfiles/files/24176984788.pdf
    • https://tipresentoio.it/images/file/kebelegudiwasufexupo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=listado+de+verbos+regulares+y+irregulares+en+ingles+pdf
    • 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_off0000be62.bin
c688189d73cf3a869fed37260abd9bf7a3021ade49a1b19f5c05e1b3306bfad9
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE62 11052 bytes
font_01_sfnt_off0000d7cf.bin
18ea9e8387c2751e619bd77f91637ffb77c668dd6a5a7b3d777621a60583421d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7CF 17880 bytes
font_02_sfnt_off000104b6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x104B6 16792 bytes