Malicious PDF — malware analysis report

Static analysis result for SHA-256 a94cd2734463be24…

MALICIOUS

PDF

69.8 KB Created: 2021-09-02 02:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: cc8351472a465ceab4d683538fb52911 SHA-1: ba0963f2c165ddc33881f2f6f5d7e7da523fb6b7 SHA-256: a94cd2734463be24a8f6073b35abd1ba7df5c9adfb129009d1bf8c9fc418879b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a phishing trojan by ClamAV and flagged by an ML classifier. Heuristics indicate it functions as a link farm, with numerous URLs pointing to PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The document body is heavily obfuscated, preventing a clear understanding of its direct intent, but the overall structure and URL analysis strongly suggest a malicious distribution or phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/20611613470.pdf In PDF document text
    • http://mikomisushiwc.com/uploads/files/41334339424.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608653b755c2f---tamupojusaturapuwafisalov.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/bogujinulixono.pdfIn PDF document text
    • http://babamoleskine.com/files/file/37769234426.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/figaleb.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/6leoh8apnpgv1c245vss86grlm/94690152255.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a1aa383be7d---barudatakorumeronirejaso.pdfIn PDF document text
    • http://retailpark.bg/uploads/wysiwyg/files/5575337182.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/a281a21b6a6987160899fb08a4dffc7a/81373240094.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/8eeef63d14f34e0f31a0973f85f0ecb2/53498564203.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083abb11fddb---30395967280.pdfIn PDF document text
    • http://asfalon.com/__files/file/46728005718.pdfIn PDF document text
    • http://wooshin.kr/uploaded/file/209350092060ee09a60ce80.pdfIn PDF document text
    • https://fcksa.com/ckfinder/userfiles/files/86884684087.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610d7bd72829f---xitupudanu.pdfIn PDF document text
    • http://wecans.net/_UploadFile/Images/file/3579099365.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/42040818776.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/c331cbd6654cf93a0f6a75f13dec485a/jawagakisubibevuzila.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/j0c3kqfqlllmd8hsqlgp3audbc/tonorifebigowiwij.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/18129797698.pdfIn PDF document text
    • http://izhar-energy.com/userfiles/file/36720830585.pdfIn PDF document text
    • http://franciscakeryandcatering.com/clients/61981/File/17590390212.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bdbd6414943---51888520766.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=self+hosted+ciPDF 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_off0000b6b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6B4 10280 bytes
SHA-256: 95c289fca1854847a2a9a4474312f40cd947350dd144bd130252f682e5b3303f
font_01_sfnt_off0000cdf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e602.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE602 14232 bytes
SHA-256: 2f48c4b0f95e3a59fd1f2de19b1c1aacb0b182155baf4103091d8f60e513b33d