Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d23e9eccc53d4df…

MALICIOUS

PDF

79.3 KB Created: 2021-09-05 14:43:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: dba48551fd3605ba43a6319470e5449f SHA-1: 86a8a6ea88fb55bd5eb0297b4b4b182335fee4b0 SHA-256: 1d23e9eccc53d4dfc8b76a30183f941a679692131df0396aba5ffbf1be04447b
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised or disposable hosting. The document body is heavily obfuscated and unreadable, suggesting it is not intended for direct user interaction but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://kondicionery-dolgoprudny.ru/upload_picture/file/madopawo.pdf In PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160dbf54080949---voperoxafilalet.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/7f03d6916c1c4c0df38232e236b58f6c/51039672049.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/2de040c3d147ec367b82112dd0520c40/sadetatozewujitez.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/63042476612.pdfIn PDF document text
    • https://fanaf.com/article_ressources/file/47573470765.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7daf2f1531---zezopanaro.pdfIn PDF document text
    • http://vlajkylevne.cz/UserFiles/File/setalikutanoletumejupo.pdfIn PDF document text
    • http://www.eventoptik.de/upload/files/robifabavifagobodevu.pdfIn PDF document text
    • https://northwestconvention.cz/data/files/mujawizifapatokituzobov.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/igfj0970rmfe2ea34pblqj87h4/74998497561.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/jofiz.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/28736811951.pdfIn PDF document text
    • http://sarkanyhajo.hu/files/file/bebizojekatatevelam.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/031711542537.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160d37b4994cca---gitaxuditetir.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/e71f7a3f9c6c650b48237fe85522e33b/34687058411.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160728a2a96e34---69935491689.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/5d5dbfa1aa5121867c76f34011c127b3/53000078583.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/i5c2hgb0cpp9nh3cp0j4dq9i67/zagalumoxik.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e6643f0f8a---35696668067.pdfIn PDF document text
    • http://netflor.pl/upload/File/14772838353.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/833d0dc373532865d7dc46172567d449/29215530906.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/d7q10cdgb63kofbjh0lt80vs8o/gafefepaka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=wireless+network+design+pdfPDF 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_off0000d621.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD621 10680 bytes
SHA-256: 4e9124b01767468dcb61013f24688ad29b7162bc2acd74239d7ccad0e0850969
font_01_sfnt_off0000ee90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE90 16072 bytes
SHA-256: 1f01341f6c30bab9135e65d8390f10dbfdbe1c59ecf0bfb1c9a95296121ed9dd
font_02_sfnt_off000117f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1