Malicious PDF — malware analysis report

Static analysis result for SHA-256 21ad44b8f0da7edf…

MALICIOUS

PDF

84.9 KB Created: 2021-09-16 18:20:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9f1c6f89ae39ff6e85c9eb48bdd2eee3 SHA-1: 7d8929470f7fb619faa3a73259e29f02a164074c SHA-256: 21ad44b8f0da7edfcbe16143eb63a74de4fea209fd6f9a8fb8efc598473008e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised or disposable domains, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and link farm heuristics supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://marsanz.pl/uploads/fck/file/kebanalivofelegavejizogim.pdf In PDF document text
    • http://svenskafik.se/uploads/fckeditor/file/devazed.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/dedakivixufovu.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/161367a0fd1f4c---dusaxopiguburojinojenakaf.pdfIn PDF document text
    • http://marasintl.com/public/ckfinderuploads/files/23652257616.pdfIn PDF document text
    • https://hmanagement.net/userfiles/file/93595948881.pdfIn PDF document text
    • http://pozitron-s.ru/userfiles/file/rajokota.pdfIn PDF document text
    • https://affordans.com/ckfinder/userfiles/files/16468989589.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/44662837378.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/87925777862.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210902205508275.pdfIn PDF document text
    • http://davcpundri.com/css/file/nukisajakarunebesem.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/pivogojiledejugu.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/zagadijazijilolibis.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/suruxebovisulazovasatos.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/60468718c14bf30fd8492b9dbe34bb11/35951287343.pdfIn PDF document text
    • https://cupanghitam.com/contents/files/5489263908.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/78807435604.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb8aae268c---nifanusekikedubisuzudoxuj.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/vozix.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/161300278e28b0---daxijajedimitob.pdfIn PDF document text
    • https://naves.cz/res/file/67032836050.pdfIn PDF document text
    • http://mweb.cz/images/file/86844637949.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=how+to+get+back+deleted+voice+recordings+on+androidPDF 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_off0000e571.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE571 10920 bytes
SHA-256: 80ecbf4dd1dd78279c2f96bbd4ecc4c193976af0ecc41efc8d30c51e0b04860f
font_01_sfnt_off0000feb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEB2 17824 bytes
SHA-256: e1d7ec0ca8586b1c35a2e0edeb91707b00909cd6f9e7a7bf853571217fc2c293
font_02_sfnt_off00012d41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1