Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7164dd7238d3f35…

MALICIOUS

PDF

70.5 KB Created: 2021-09-24 23:27:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 96627abb37efb0ea09085d898e8f4c65 SHA-1: b98d949bbba8651b28fb3a5a197c09475b20cf1e SHA-256: a7164dd7238d3f35aea078050fc9053f127fc0d15e5cb9d79138d71b16a2784d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the true destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or redirecting users to malicious content. The primary attack pattern involves luring users through a malicious attachment to click on these deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://musikkursus.dk/userfiles/file/54626528865.pdf In PDF document text
    • http://lexen.ca/userfiles/files/20196862501.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/4175795591.pdfIn PDF document text
    • http://gfk-schwimmbad.de/i/File/wusaluboxiwexiz.pdfIn PDF document text
    • http://rvhifi.cz/files/file/jeroxas.pdfIn PDF document text
    • http://lamachine.nl/userfiles/file/88552243474.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/zodipagojolozemope.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4e8faec3b---77931531292.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a68b9f0724---ranono.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/28006884872.pdfIn PDF document text
    • https://owop.challengersports.com/userfiles/files/63701858673.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/wapobebijawuvukod.pdfIn PDF document text
    • http://wonderpanel.com/app/webroot/img/file/92714853383.pdfIn PDF document text
    • http://elfobchod.cz/foto/Image/file/46167771999.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/suruf.pdfIn PDF document text
    • http://grabnerestriche.at/42324873495.pdfIn PDF document text
    • http://chapelguild.com/images/usr/wopepudejisumejex.pdfIn PDF document text
    • http://girc.ncue.edu.tw/ckfinder/ckfiles/files/93618048881.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f86451fbea---jezewolikibugofukijuvuxur.pdfIn PDF document text
    • http://apartament-krokus.pl/userfiles/file/ribiragidamewemep.pdfIn PDF document text
    • http://chinalabware.es/d/files/86899912332.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/7432f0e0bfb0f945e6f70c63b51df1a2/61469632236.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/30754050017.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=negative+words+that+begin+with+kPDF 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_off0000b29d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB29D 10844 bytes
SHA-256: 4b901c2e168956310138365358ad51dbcc3ac95519e3d338729d30b6ae0007f6
font_01_sfnt_off0000cb71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB71 16016 bytes
SHA-256: a7e8150571e0888024a5a453f3080e5a4af5b7510e94e5d0a8e3220538ac6433
font_02_sfnt_off0000f446.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF446 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1