Malicious PDF — malware analysis report

Static analysis result for SHA-256 0728618b7d8751c0…

MALICIOUS

PDF

80.5 KB Created: 2021-09-11 02:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d1252eeb736a653abc17a3c397614e9e SHA-1: 3013dc2da739a59d71d8fcae816672a17288c34a SHA-256: 0728618b7d8751c09471c1b1150a982d12b6a08193098b52beabe58b371713d3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous external URIs, many pointing to compromised WordPress upload storage or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to lure users to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://smidgel.ru/uplcv?utm_term=happy+bay+apk+old+version PDF link annotation
    • https://niboparis.com/upload/fckeditor/file/1630767224_1.pdfIn PDF document text
    • https://eurochen.com/UpFiles/WebEditorFiles/file/raguvo.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/f7f88da8a130df423289ec2f6e9dc071/89579191824.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/pumeda.pdfIn PDF document text
    • http://corse.annuaire-regional.com/ckfinder/userfiles/files/zoxetipi.pdfIn PDF document text
    • https://rh-h1tapi-turbo.com/contents/files/tobitugewemedoxovozibubij.pdfIn PDF document text
    • http://fotografoenricogiampieri.it/userfiles/files/76709551912.pdfIn PDF document text
    • http://spprp.pl/userfiles/file/4098785556.pdfIn PDF document text
    • https://birutelorasin.com/contents/files/10090099259.pdfIn PDF document text
    • http://sydjpg.com/images/upload/file/20210906_095627_192.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/29892630539.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/riton.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16132aec2b0ccb---sopidutefezarulujedawulil.pdfIn PDF document text
    • http://chithanhplastics.com/uploads/userfiles/file/67835906622.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/29785632288.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/waluvijaworimep.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/64638156562.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/sexosakalud.pdfIn PDF document text
    • http://azstorestudio.com/uploads/files/83772872789.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/tegesisunotiwekotizizovoj.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/sufowawuliba.pdfIn PDF document text
    • https://y3stwk65l-mn9.com/contents/files/59932252261.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/trmmtf0m7fk0nl52kon4t984j1/kijagetavilamadab.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_off0000d4df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DF 10688 bytes
SHA-256: c3609aac44b04fce34df6250c97a80b368d16202c40b836d2cbe4cf2de108372
font_01_sfnt_off0000ed33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED33 18128 bytes
SHA-256: 6caf7011381903ca933550c0b238102b3663c0786926d01bd96628f882eab9f9
font_02_sfnt_off00011cb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1