Malicious PDF — malware analysis report

Static analysis result for SHA-256 851d5045a826727b…

MALICIOUS

PDF

86.4 KB Created: 2021-06-30 08:21:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: faacaa785285a3a381cf644700c7c4c5 SHA-1: eb5b229320fe95f48bdecf7e2d5136aec9903c81 SHA-256: 851d5045a826727bdbfa9a75a01f1163f1a1814c298d3bdb859af16c15257a81
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the link farm structure is a clear indicator of malicious activity.

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 http://instant-image.net/UserFiles/Site/File/90542116583.pdf In PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/4fc7b32ab71a0d452d5ac520c0d17a91/70874204610.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/97076817476.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/37770937231.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c77f06df6c3---67050271097.pdfIn PDF document text
    • https://bamfieldrental.com/userfiles/file/6168960420.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/1524ce7c44a77f3151d500ed083d7d47/farejezujozivizo.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/481a826dd8080fec3f331bc7fda5402a/navapukubonarefuzalol.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/bddb2d7f492a5a9425ec09298754fd18/zipesoxazeronobipi.pdfIn PDF document text
    • http://quanhoangtsi.com/upload/quangtri/files/13657802017.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609880803daae---13266841642.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/54112238050.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5944814e7f---7045952554.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d78124c2d80---bodupiwifapabaxazefesuba.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/fc06fe8677b18ce4e29a7e7662270837/12277500061.pdfIn PDF document text
    • http://magyaringatlanadatbazis.hu/dev/_user/file/ditebigokexozavo.pdfIn PDF document text
    • http://silmalogistics.com/sitename/app/webroot/uploads/ckuploads/files/jupawenogulusifibiraji.pdfIn PDF document text
    • http://abpaluso.com/upload/file/kalezasar.pdfIn PDF document text
    • http://megat.pl/uploaded/fck_files/file/17769058113.pdfIn PDF document text
    • http://amandamaitland.com/images/file/44644917848.pdfIn PDF document text
    • http://ohsongpharm.com/ckfinder/userfiles/files/luwosevuwufamamebotekalon.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/52286a79fb2b31f5abb226d7ebaeca48/9360621037.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a972d09a0c---lizugunav.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/fpu51494g3hpq4de066ka4nqh7/37565839342.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/9614de12f793e2baca0a6876341871ee/15735539984.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=traders+guide+altoona+paPDF 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://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_off0000ede8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FF 10632 bytes
SHA-256: 628500720cfdfce30277d6a562d78897f0743c5d4a5bab0ca2d14b64a0cb14e4
font_02_sfnt_off00011e2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E2B 17576 bytes
SHA-256: 7c9ef9f9ad8ff28da475cf31652a0279870b31eb023357fefb118b08fc60ce70