Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b8a4c0cb397368b…

MALICIOUS

PDF

88.1 KB Created: 2021-07-02 20:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 55d5a052b1b0d104983759b853087ece SHA-1: 09ea296cd27f4666eb9963dc0896eb98c413ec26 SHA-256: 9b8a4c0cb397368bae3e45cf5d9c7448eb3f41794835e310ca4552f91f7c03c6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document's primary purpose is to act as a link farm, potentially for SEO manipulation or to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://crewmak.ru/uplcv?utm_term=watch+dogs+1+download+android PDF link annotation
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/861333e7fc2a3df50a446468730fb2bc/nanis.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160aaae0231fe3---sivisuxozamasus.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/xodavinino.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/sowotefumipa.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16083a454cc7de---xinedegusixapop.pdfIn PDF document text
    • https://diaspoassur.com/wp-content/plugins/super-forms/uploads/php/files/12f198a9a20d032cb258a2aeda54d713/65985366098.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/82501646244.pdfIn PDF document text
    • http://prunay-en-yvelines.fr/ckfinder/userfiles/files/99065509951.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/tbo2vvvpuqv9k74c2ucnk6r6q7/wuvus.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/kavajozafoxewiw.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/099dbf5b20dc8d95a8b59889fb2f77f3/videvoburitogafimowidim.pdfIn PDF document text
    • http://firegallery.ru/img/upload/nitupajipafalugide.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/73018819569.pdfIn PDF document text
    • https://bazab.ru/ckfinder/userfiles/files/24326428203.pdfIn PDF document text
    • https://dbmotorbrokers.com/userfiles/file/siduxanupurob.pdfIn PDF document text
    • https://yssnewlessons.org/UserFilesTwo/file/77907242202.pdfIn PDF document text
    • http://redfordunion70.com/clients/869360/File/totewosafosijofeguf.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c86e650556c---2524789598.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/77277199555.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16072ad21c6173---54586995630.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_off0000f2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2DD 18904 bytes
SHA-256: baf48c4e754e2889ec9731a381901464aca0dc37b5dd26a6a8dd2cba3a089dff
font_01_sfnt_off00012306.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12306 10648 bytes
SHA-256: 4d3c62ac709ce0783122bc8a63ac879299db3f4a47947e19d39fa7c5eba347fe
font_02_sfnt_off00013b40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1