Malicious PDF — malware analysis report

Static analysis result for SHA-256 25d39bca995c0367…

MALICIOUS

PDF

73.8 KB Created: 2021-10-14 05:35:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 25cb471c3431e6f6c882ff04ca6488a9 SHA-1: a15275f117cd835d3a2f6805d4383a7b49501180 SHA-256: 25d39bca995c0367f83d6c4cf570e3efad9b811871b4d435fe1061759c20b6db
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous URLs, many pointing to potentially malicious or unknown domains, supports the phishing and malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://pieseautocomenzi.ro/userfiles/file/54228792573.pdf In PDF document text
    • http://aexpress.lv/index/images/up/file/44863478051.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1616664c82ded8---tapugesemiviwedivug.pdfIn PDF document text
    • http://trungtamdaykem.vn/Images_upload/files/61607408635.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/22308951093.pdfIn PDF document text
    • https://qkon.ca/images/file/rasobomelusulumiduvul.pdfIn PDF document text
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210907192708.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/wekukumofetojobuxewu.pdfIn PDF document text
    • http://kompletucetnictvi.cz/files/file/93905370817.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/kexezuloxamubobo.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/93044559231.pdfIn PDF document text
    • https://mobspace.xyz/web/img/podborky/files/2942460107.pdfIn PDF document text
    • http://bodybybodyology.com/ckfinder/userfiles/files/87551929382.pdfIn PDF document text
    • http://lamarchesainterita.be/lamarchesainterita/imgdb/news/files/68220701763.pdfIn PDF document text
    • http://dongphat.net/upload/files/napudiw.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615fb8af0b441---kezadeweni.pdfIn PDF document text
    • http://bioaec.com/userfiles/files/tuxagamipew.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/nelifug.pdfIn PDF document text
    • http://luisacortesearchitetto.it/userfiles/files/bulibelezug.pdfIn PDF document text
    • http://cdkuysuujk.handysociality.com/upload/files/93585441266.pdfIn PDF document text
    • https://grouptm2.com/contents/files/59568842631.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/760806f52426f37d27285b674593add4/dinijupamatoxalesidafez.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/31135713110.pdfIn PDF document text
    • http://phannhan.vn/files/usersfiles/files/23744472605.pdfIn PDF document text
    • https://pointswestliving.com/ckfinder/userfiles/files/wubijaludumagijej.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/7xhmvLXWVJc/uplcv?utm_term=nabokov+strong+opinionsPDF 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_off0000bf3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d74d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74D 16368 bytes
SHA-256: 096c549b42d3d74e3e1e18c3d1a7df5f5585486f724aa40cc9bb7ee37bef9d27
font_02_sfnt_off00010114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10114 10524 bytes
SHA-256: aec09888e0dd716dda493bb059b2cafd1ce640be823762ed3f99691464b54c8d