Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c21c50598516b76…

MALICIOUS

PDF

91.8 KB Created: 2021-07-03 21:28:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d19dc7900b1b885061c1c41c43068acf SHA-1: dfa9a255aade837c525ecd8a32cd7d55e1234292 SHA-256: 4c21c50598516b7682494e4243b91bfc34cad4f3bf0b384e85894f6554e4ae72
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document contains numerous links to external websites, many hosted on compromised CMS upload directories, suggesting it functions as a link farm. The primary goal appears to be directing users to potentially malicious or phishing sites.

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 https://infrive.ru/uplcv?utm_term=free+cloud+mining+no+investment PDF link annotation
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607f013ba5728---puwoxanujeremuxo.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b77e60db79a---7894105935.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/5f3753612e259e4424265ee2c58712ec/biwerit.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c19a47e706a---deludobuxonixewafife.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16088cbd5e5021---sorerofofa.pdfIn PDF document text
    • https://ive-cal.it/file/27095861955.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/08ae166c200c5b1acfce89fa21f5137c/82549644281.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/160813ef740ba3---83184166421.pdfIn PDF document text
    • https://actor-conseil.com/files/file/sadasilabosutadip.pdfIn PDF document text
    • http://vrtaspol.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/66734469613.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/b81c3b30351f625260e51bd1a49414ad/8903278141.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a397a5098b---xodopadivexaketavozat.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/wopenebus.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab19f9bd7a---99513346162.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16098b4c66510f---6628643975.pdfIn PDF document text
    • http://daiichilogistics.com/uploads/news_file/rekofedugoruturev.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210513192814067.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/mvo7bgr4vd8ihoavvso0ongud5/72944174092.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/7762e490feec14d99db3782ba27ba290/52852749933.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097dba02533f---lufonoxedefupimakakiwaz.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/3e84193116ac445482f97d45d9fcd7a8/80051024076.pdfIn PDF document text
    • http://farmina.ru/uploads/files/32890609292.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606c800cd4e41---29939524492.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/ql3ac9rlmsomgsvh8ujg0ja5p6/jakerinugaz.pdfIn PDF document text
    • 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_off0001016d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1016D 18080 bytes
SHA-256: 20b688678de99548b05975c638a65c13d7e689159b1be40bf59865a77383de93
font_01_sfnt_off00013146.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13146 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001495d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1495D 10692 bytes
SHA-256: a85564702cc62ccc582140552d2a147dfe6e028cd21d1d75567363ce851ab595