Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4482bea2d29c136…

MALICIOUS

PDF

86.9 KB Created: 2021-07-07 08:18:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2695a099310dcae480c110a02eb86c3a SHA-1: a9ea7008924901e7c2bd75007d865f568ac848a9 SHA-256: a4482bea2d29c1365ea0026dc65b806bb02a172d7f00ddff7f52646a68aeba3a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting it's used for phishing or malware distribution. The presence of embedded URLs and the nature of the heuristics strongly suggest it's part of a phishing campaign, likely attempting to trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://krisoc.ru/uplcv?utm_term=collage+maker+100+photos+free
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160cb030531d02---98035423413.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d5154612130---48316119581.pdf
    • http://dentherapia.hu/files/file/varopajazugaz.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/8d29c3e4c116e19708dfce099640b1bc/15263313696.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a32a4c765---kilera.pdf
    • https://angelsstaff.com/uploads/file/97960956374.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/03815614c6d9c5c2677a93d33f9db648/49677407251.pdf
    • https://nanyangtextile.com/userfiles/file/wilujukesa.pdf
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf42884ab9---64362174863.pdf
    • http://ottotech.center/userfiles/file/69117302117.pdf
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/4366tel5t58rhu5jc70rr03s7l/ketusinolapatakenube.pdf
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/a8ab4e93a65d981072acea39333d5193/29022731853.pdf
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb0b0132d0c---37246899050.pdf
    • http://asude.istanbul/ck_images/files/vokujizupok.pdf
    • https://giustofiori.it/file/98862167031.pdf
    • http://driver-jazda.pl/upload/file/30281793317.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160820e9e50cab---80692785446.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad8d25b8dc9---18764299358.pdf
    • http://pwr-tech.ru/userfiles/file/jofirukokivosumu.pdf
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160905afe16cc8---zobanoxafadinen.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16087bc79ce38d---bakid.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/ccdch87i4v1p016ohser2fgjt0/jejuj.pdf
    • http://sun-green.be/ckfinder/userfiles/files/lumatavev.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd27f212ae---28865332979.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/8rv9bim5vjkmrden481h8pi9c6/mukuzefepigefa.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_off0000f061.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF061 16792 bytes
font_01_sfnt_off00010873.bin
2bfdb5e69bd0561a069a7b881c7296e74a72d8a607585f02535868271f5415f4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10873 17060 bytes
font_02_sfnt_off0001350f.bin
bc398b5f12ac8a78af76784996ebe6bf1f88d1a5334f17b4f38847ff968a3b14
pdf-font-stream PDF embedded font (sfnt) at offset 0x1350F 10908 bytes