Malicious PDF — malware analysis report

Static analysis result for SHA-256 f935a04d5b3ba512…

MALICIOUS

PDF

85.8 KB Created: 2021-09-08 09:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 42497f3b947ab72360906d05951aa931 SHA-1: 366deff1824ae529abe7b8e71c4ff4ead25fa976 SHA-256: f935a04d5b3ba51211eb8b66209c4d76226f45e23885a6b2f5e3dd0a3bc7086c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/783a87d4fba38874148af4ecb194005a/wulijasebovupigijiwakem.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/16086e5276c9d9---wutebulapon.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/m2t6soi8mct93r5f8des7uekh6/36179802805.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160aab0e40e1d3---daxolinodurawala.pdf
    • http://precedent.by/_newsite/images_from_html_editor/file/fowasuruxusowi.pdf
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/2ubvpn31q2l7q07fvkcuhic73f/fujaxisukupakoragaza.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/h59jvporrj4ita2uopogctrfim/82683342361.pdf
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cdd3ac6fc63---dovuwadema.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ec9de2bb2---13600620869.pdf
    • http://gostinica-domodedovo.ru/files/menatijavuxikilaf.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ca3c9f18bcc---94531199393.pdf
    • http://wecans.net/_UploadFile/Images/file/jesevoxajade.pdf
    • http://sonnenheizung.ch/fckeditor/editor/images/file/furigi.pdf
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a2071a687d---gewadubinekipuziwom.pdf
    • https://polnische-zaune.de/userfiles/file/jugugiwokiduvogofi.pdf
    • https://energooptima.hu/upload/File/munobus.pdf
    • http://windmill-bv.com/userfiles/files/ponevuze.pdf
    • http://avanti.pl/userfiles/file/9456318006.pdf
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/9bdf96bcbad2e79f65b779a5c8ccb83e/8591635298.pdf
    • https://searchlink.org/userfiles//file/zivuwirodikopewer.pdf
    • http://cheers-gifts.com/userfiles/laviwemipulu.pdf
    • http://cainghienbinhduong.com/uploads/userfiles/file/88604163138.pdf
    • https://konferencii.ru/js/ckfinder/userfiles/files/88983659419.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=programa+para+traducir+textos+de+ingles+a+espa%C3%B1ol+en+pdf
    • 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_off0000e4bb.bin
9505046ca4aeda9dee726e6cfb09ee88b62e8d6d1f5191d601c0a90c89ede05d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4BB 18588 bytes
font_01_sfnt_off00011416.bin
e7d329cb5d0ebe3159bc452b85b563c91521844d5aab5d062861ee8f47e1671a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11416 11372 bytes
font_02_sfnt_off00012e7d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E7D 16792 bytes