Malicious PDF — malware analysis report

Static analysis result for SHA-256 78eb581605bbf53f…

MALICIOUS

PDF

84.7 KB Created: 2021-09-07 06:01:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 89e9ffc51e8f61b0e8bb52f17b7fdf60 SHA-1: e3a747a641fb7ae9afeb0f6b2a6c64618f7428bc SHA-256: 78eb581605bbf53fc04e1e8cf6370bb943fe02b6187ac5558eeb1a7b8f86d430
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The document body is heavily obfuscated and unreadable, but the presence of external URIs and link farm heuristics strongly indicates a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b770f6d057---tezunudanar.pdf In PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/78942956382.pdfIn PDF document text
    • http://dogninja.com/userfiles/files/fudim.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/6f418c3dd5c2377dd6342699e62253da/wotulokelolebaninizit.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607be4dfcbc54---2433077776.pdfIn PDF document text
    • http://rcot.by/pics/files/28641137795.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/32380535351.pdfIn PDF document text
    • http://mishelik.ru/userfiles/file/48957832042.pdfIn PDF document text
    • http://csc-0411.com/userfiles/file/20210702201059_gi34pc.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/43591714625.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/7irvl4d4oommnvu1ok4bf5ute3/bifepojarawud.pdfIn PDF document text
    • http://tranhdaquydep.vn/upload/files/4529762215.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a01204991db---35004071706.pdfIn PDF document text
    • http://whscardinals1963.com/clients/9/9e/9e5fab02d16e7113a74bdd4e7828f974/File/39620243200.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b77bd35606---43138431288.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-7-27/20210727083057244208.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ab09d394a---68263984353.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/rivinonixufaramudovet.pdfIn PDF document text
    • http://kubabus.cz/novy-web/upload/file/giwerax.pdfIn PDF document text
    • http://splogservice.ru/content/files/pagorelaweluz.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/96985404346.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=atx+450w+smps+circuit+diagram+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_off0000e123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE123 18796 bytes
SHA-256: 5cfd82f1c6e23850b57a6300d1f2bf646d870256dc7a6c176e181b9ef9de10f0
font_01_sfnt_off000112b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112B0 11164 bytes
SHA-256: d7c3ee7dcf6f5ff16dd21a74a8c3edb1c67826b15f89474bf21df1855c283721
font_02_sfnt_off00012ccf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CCF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1