Malicious PDF — malware analysis report

Static analysis result for SHA-256 8745c1dc70cf1d65…

MALICIOUS

PDF

80.9 KB Created: 2021-06-17 13:34:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 7e199018248ec3cd234d486637fdbedc SHA-1: b11c6e20ac45c5299dfbf229b6d4a9e094947e1b SHA-256: 8745c1dc70cf1d652a611b38dfff63142e3a94c5f518928b1bda2fb880853e18
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress upload directories, indicating an attempt to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and appears to be junk data, but the presence of numerous external links and the high confidence detection scores are sufficient to assess its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/rvdecc2tdhudq28nrhtb0fl918/dizunevexixifujugu.pdf In PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/ks2doeol4vndr5a0nkbhbcprfu/27319185942.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/69ced5f5de7cdf6d8c992a493216da5a/9092427898.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac174b7c3db---53548552398.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0cf72b9fd1---kurebalobememamujaf.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/73fa748993ef10299f0a608cb562ae3a/90645077766.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/a98000cef3712ec7d169428f30913466/gutexefomidetumuwokapeno.pdfIn PDF document text
    • http://iwishop.hu/file/gasugefis.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/d0331596f967422c28bbede508cefdef/98785899449.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/dj15vjd4vnsb23g6ovb7s8ec20/9299292721.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a6db9b737a4---91228393796.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608053bca57cf---sinelamuwakesim.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/a92gap2jrmh45rs4lo9ivd0a5v/vusezoxidaviresojutevuvi.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/95825128553.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/191itplk02u3tufige39ogephp/51206409474.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/wevurikuzijowawilizutano.pdfIn PDF document text
    • http://lpkgoodframeupvc.com/userfiles/files/wukezoje.pdfIn PDF document text
    • http://yonseri.org/userfiles/files/bovitomopatatefekow.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+find+all+grubs+hollow+knightPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fe80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE80 5424 bytes
SHA-256: f0e258bd819b332450cff03b8adce7a86873e11c12624c04a7491bf7544fc022
font_01_sfnt_off000110fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FE 10596 bytes
SHA-256: bbbb599058429790bfcf6a91aa6548d8c5881bca9c3430e0cb88cf87ad542b47