Malicious PDF — malware analysis report

Static analysis result for SHA-256 90de35fed90df939…

MALICIOUS

PDF

86.5 KB Created: 2021-06-30 05:01:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 34854a639df5ef6689a02f138d4c9c7d SHA-1: 5d75833fc7ac45c87687f4ac4633dd06497c3b2e SHA-256: 90de35fed90df939d24e9d2714913f5c53ba93388e2f1fcd6ededa5a4da73b78
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, indicating an attempt to distribute malicious content or conduct phishing. The ClamAV detection and ML classifier strongly suggest malicious intent. No scripts were extracted, but the presence of numerous external links on potentially compromised infrastructure is a high-risk indicator.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072ac4f94c4e---21995027801.pdf
    • https://fourseasons.events/wp-content/plugins/super-forms/uploads/php/files/4735ee72b92b7019a33a42c8703bab2f/ruwitodubij.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097dba02533f---lufonoxedefupimakakiwaz.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/0b4dbecb58d9fcbe60d66800b7ed5aff/76696621449.pdf
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608afe2e18a83---42145474963.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/62122975eaaa9dc1098c24f156a90213/24378674060.pdf
    • https://publicbridge.pl/userfiles/file/zebuvokonipalozado.pdf
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/r1b93kke8ino3uodjsui2h87so/lukapir.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091743015bc0---dusavuruwozab.pdf
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/77edfaf91032749ae4c7adcb576bc41f/3080045187.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/23461a3e4251dbedd830212e57544138/83270072906.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/7plg7munasqann3r5p1fq367hf/41951110417.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea4b10f048---roraxavumimojafaxufu.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160abe7f6e4238---56383981068.pdf
    • https://aravlicraft.com/cmsCart//upload/file/5942149751.pdf
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/6c87284dc9bfd8aeeac0e621072093ba/tiwed.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a31bccbf221---funuropabefibifasik.pdf
    • https://melz-feu.ru/upload/1377738957.pdf
    • https://arerp.kr/data/file///lowewaviza.pdf
    • http://boldino-hotel.com/ckfinder/userfiles/files/835490934.pdf
    • http://vamaconsulting.sk/userfiles/file/rakekigina.pdf
    • http://taeguektour.com/FileData/ckfinder/files/20210623_8BB0EFA3320D1E5D.pdf
    • http://chieusangducphat.com/uploads/userfiles/file/nekudasi.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/85aead2b3de5c1f1e531763fb093149a/19012097252.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+make+dark+brown+acrylic+paint
    • 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_off0000ef81.bin
35e79290493ef0fec11966429659cb4f283529a2bdc464ac01a6d80aa44d6828
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF81 17060 bytes
font_01_sfnt_off00011ba9.bin
42fcb66b5c7d63ec18914b08400a5b32de34693b90f78e63279b0850a2e13f9a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA9 10928 bytes
font_02_sfnt_off000134b7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x134B7 16792 bytes