Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef1f2c147740eb90…

MALICIOUS

PDF

80.8 KB Created: 2021-09-08 09:23:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ac26217e0f6d717cc0ebb5564957a092 SHA-1: 96d8790777ec489947de74b5e53b2dc50b618014 SHA-256: ef1f2c147740eb90813f0c5492547f7094cde3ac5ed4f94bd64ab969e99c85f4
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 or disposable domains, indicating a link farm designed to lure users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the nature of the document as a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://shop-ecobati.com/medias/upload/files/28312713367.pdf In PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160de18543e96e---kitilonogozuvudogilefere.pdfIn PDF document text
    • http://bociany.sk/media/file/dadikubifojimoja.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/24595869459.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/65376919372.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/kuwinomasamul.pdfIn PDF document text
    • https://vico-inmobiliaria.com/ckfinder/userfiles/files/75735484.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/tizedomipopojejasax.pdfIn PDF document text
    • https://vnnc.vn/img-hdmedia/files/20256334379.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/lerixiboxitad.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608593f9a90a6---lanozoxuveza.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/694ad64ab9629789045397345d911c29/nakalafinoruve.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/nokuzigude.pdfIn PDF document text
    • https://sitpchemcieszyn.pl/_sitpchem/file/kenejusupebiteju.pdfIn PDF document text
    • http://candemdientu.com/Images_upload/files/54450254699.pdfIn PDF document text
    • https://traiteur-troyes-mariage-buffet-aube-10.blaisot-traiteur.fr/ckfinder/userfiles/files/xejakuwugalizibuxetu.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/fa70fb9e899f7706f779d466b57c255f/lukunuwibuzazilixexameka.pdfIn PDF document text
    • http://caramelitos.sk/files/18113606561.pdfIn PDF document text
    • https://zebcom.in/userfiles/file/futimapupolol.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160adb3c068d70---17105525579.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/tudabupojopi.pdfIn PDF document text
    • http://china-zzld.com/uploadfile/file///2021070606512578.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/tipovuzi.pdfIn PDF document text
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/refukigojipiriwemu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=dual+clutch+transmission+working+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_off0000d958.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD958 11212 bytes
SHA-256: ba25a4b99e588e758e9e9343954aacae1b37beb0240c4b8a894826b5c92dd22f
font_01_sfnt_off0000f34a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF34A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5C 16296 bytes
SHA-256: 8dd492d9629382d7b3075a95c8ae7847ad3c832e52f618497d362af1d8659f78