Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fcf5611de39eb5b…

MALICIOUS

PDF

69.5 KB Created: 2021-10-02 09:29:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 3fad2dc3de10c4c6d723225b22da703b SHA-1: a0097d38f23d2b45cd8eb4fe22198fb3a90c0d97 SHA-256: 8fcf5611de39eb5badfbc57972888571d11aff763bf73e5cffac568d105792c7
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, many of which are hosted on compromised CMS platforms. This suggests an attempt to obscure the final destination and potentially distribute phishing content or malware. The ClamAV detection and ML classifier further support its malicious nature.

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 http://pphu-joanna.pl/fckpliki/file/sapiwowibiru.pdf In PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/78cb192b063af4cefa1300a0bb42259b/wakosomumu.pdfIn PDF document text
    • https://autonoleggioassereto.com/file/sadenosejunuxif.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/27029344119.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f449fbdfb6---31440487870.pdfIn PDF document text
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/vewefojoreloxeno.pdfIn PDF document text
    • http://sushi-belovo.ru/files/81859985166.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/79327737260.pdfIn PDF document text
    • http://centronegozi.com/public/zulitotebelazavunuzud.pdfIn PDF document text
    • http://ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/fisorigozubisazulikes.pdfIn PDF document text
    • https://lengthening-sldf.com/userfiles/file/29384418199.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/75157d1878765665c134c578eca40190/rusetafamorifixinevi.pdfIn PDF document text
    • https://sicurezzaips.it/uploads/file/34296806083.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/lapesesukerigejodez.pdfIn PDF document text
    • https://mackbeks.com/files/file/76757991779.pdfIn PDF document text
    • http://daithanhnam.com/upload/files/vunoforajonuxofifej.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16139296acf049---78595353384.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/2n63ihj1ik12a1ec25fph2pivn/gisilejexiz.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/65861679433.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/41642581933.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16144f3c434700---83429743961.pdfIn PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/43408570482.pdfIn PDF document text
    • http://anm-av.de/uploads/files/91819253626.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=nfs+most+wanted+full+download+for+pcPDF 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_off0000afe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFE5 15620 bytes
SHA-256: 3b1b34ab0e11a762669b425a478ee4673854edcba03c45814caa8c2ffe121628
font_01_sfnt_off0000d75f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD75F 10852 bytes
SHA-256: 01ce1ccf9b9fd75f18b7d9be4da58622d1ba761f825df0593d8372f1f7d0c66e
font_02_sfnt_off0000f086.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF086 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1