Malicious PDF — malware analysis report

Static analysis result for SHA-256 d740ef549f19c1d4…

MALICIOUS

PDF

88.1 KB Created: 2021-09-14 09:44:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f0fed8703e7224e6fb67cb586198f3d8 SHA-1: 3294c6f5249e86d797c3a402b841c1fc391027a7 SHA-256: d740ef549f19c1d473dcc9a7c71e34d55fd263227de1aa14a9c3c4b1cc15cf26
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to various domains, many of which are hosted on compromised or disposable infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and link farm heuristics suggests an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://bepcongnghiepphuchung.vn/userfiles/file/safokopudidexez.pdf In PDF document text
    • https://rh-h1tapi-turbo.com/contents/files/1182566252.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/63209673939.pdfIn PDF document text
    • https://kit-veron.my/ckfinder/userfiles/files/lezegidagig.pdfIn PDF document text
    • http://riverside-plaza.com/upload/userfile/files/jikiwaxumo.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109070656296930.pdfIn PDF document text
    • http://envigest.cz/upload/file/tumamebiwofekowaniwuj.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613fea92cdfe1---85868092977.pdfIn PDF document text
    • http://kartinatv.org/uploads/files/napirubifagozoxusixuti.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/17314477445.pdfIn PDF document text
    • https://membermimpi.com/contents/files/sufavifinakinuki.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/09ea5e7f7cc0c6eeb5bf3acad792ae66/fusepemokala.pdfIn PDF document text
    • http://paoladebenedetti.eu/userfiles/files/kevixivi.pdfIn PDF document text
    • http://hanasushimenifee.com/uploads/files/30743829636.pdfIn PDF document text
    • http://kimdaiphatsteel.com/Images_upload/files/nemotezifaxavuf.pdfIn PDF document text
    • http://hotelborgodeipoeti.com/userfiles/files/nibuniwagolofodifimalos.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/48770610216.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613db4c9705d6---zodiridokasonulizukakadu.pdfIn PDF document text
    • http://sameiroeventos.pt/ficheiros/14287045146.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/62554258043.pdfIn PDF document text
    • http://hotelrealerimini.it/userfiles/files/7759411296.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=apk+jurassic+park+builderPDF 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_off0000f4a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A3 17976 bytes
SHA-256: 93d5d0c9ce1602dce65d53257e0c7b9483c9b210378cf1544c8a878db923e67b
font_01_sfnt_off000122f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122F2 10628 bytes
SHA-256: f4b1d39c4258466353fa8249f1f50a89fd62d0d1de8345d3c9468c2aea54d4da
font_02_sfnt_off00013b24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1