Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1a8eb71e13c774d…

MALICIOUS

PDF

89.9 KB Created: 2021-08-03 17:07:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b6d7723d57498e4202c75ff3fa554272 SHA-1: ca79060d1ec1d67aa7d58d1b38f340b33260b9d4 SHA-256: a1a8eb71e13c774d0d41b71a0bc07359eb2978623497f1e457a6903431f90ac0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to external resources, many of which are hosted on compromised WordPress sites using the formcraft plugin. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links to PDF files suggests a link farm designed to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607191f3d58aa---mikolopasunuxukorewujawos.pdf In PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/e23f16ecdc43424df5e4bef7ede64214/zakugij.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/795371607.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607571853740f---68472352087.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160dee6427a0c0---26823928398.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a184ebcba6d---38312017019.pdfIn PDF document text
    • https://aromamarketing.md/img/files/7086869358.pdfIn PDF document text
    • https://mimpiindah2.com/contents//files/muralufebudexevofu.pdfIn PDF document text
    • http://hyperasp.net/userfiles/file/fuzosibekatepexiredasajum.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/97280239113.pdfIn PDF document text
    • http://altinay-law.com/images/file/68310128601.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/99049640192.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/4681559611.pdfIn PDF document text
    • https://ebooksweb.net/files/file/87718904804.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4b1cb602c---62158045272.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/f2aaf766b4c59ffa40d0b0df0922af92/17664564401.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210611_85D49C38100DF935.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/740311f50c64159001d7cbd7172e0739/sevuxisozisuzasawowolaf.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096b5ccb3e68---xivipezusolefegezorug.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/7907635800.pdfIn PDF document text
    • http://tw-sincere.com/upfiles/editor/files/75763985914.pdfIn PDF document text
    • http://raffaelecavazzoni.com/userfiles/files/8957984800.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=mkvcinemas+film+downloadPDF 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_off0000faef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAEF 17868 bytes
SHA-256: c9572893a644de9cd89430bbd22ac79e64c037ec6027662b6b200c5580d9262b
font_01_sfnt_off000129b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000141c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141C9 10676 bytes
SHA-256: ccf15da2e9f37bd613280ee393bdd5aed9334fc16a8b8c0fbaec47af1e24be8c