Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4a92f7c7f014246…

MALICIOUS

PDF

80.4 KB Created: 2021-10-09 12:43:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6293abcc0ad6670d9676fbf03148730e SHA-1: 69591dbcd4057260d663f58830797c2a64a89815 SHA-256: a4a92f7c7f014246bb522781a1bf0cca431836b711526e8e30c631f53b7421cc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically identified as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised CMS upload storage and disposable hosting sites. While no scripts were directly extracted, the nature of the links and the 'link farm' heuristic suggest an intent to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://yomadesign.com/userfiles/Proj_Name/files/90667570582.pdf In PDF document text
    • http://alrehabourhome.com/userfiles/files/gesiwobosuki.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/161417dd319dbc---57297373635.pdfIn PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/pinodidulowosujukivesa.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/24562135612.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161458bef5e840---49016861925.pdfIn PDF document text
    • https://santa.my/images/users/00000000/files/dulikurumapi.pdfIn PDF document text
    • https://sportscientistsviews.ijmsir.com/ckfinder/userfiles/files/kafupabobasef.pdfIn PDF document text
    • http://kaies.net/upfiles/file/lupupizilo.pdfIn PDF document text
    • http://traktorpulling.de/ablage/userfiles/files/63027565030.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150cf1c40c7d---tanimag.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/67779538854.pdfIn PDF document text
    • https://novamakine.com/upload/ckfinder/files/tuwudanitejabofurilo.pdfIn PDF document text
    • http://chinastom.ru/userfiles/file/jegerevuzotalunavuvur.pdfIn PDF document text
    • https://batdongsandothanh.vn/luutru/files/fubunebojuvidabebupo.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1615f87c12f49a---jixabepad.pdfIn PDF document text
    • https://supremeroi.com/FCKeditor/file/govesenuzorexonikiw.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/34402394386.pdfIn PDF document text
    • http://jl-vacuum.com/upload/files/piwegaxozovo.pdfIn PDF document text
    • http://studioarchperissinotto.eu/userfiles/files/79996541920.pdfIn PDF document text
    • http://swaptoys.org/ckeditor/uploads/files/kijetepoziweles.pdfIn PDF document text
    • https://mimpiindahsatu.com/contents/files/dovabepikare.pdfIn PDF document text
    • http://rasmesafar.net/basefile/basefiles/76998238328.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614edce9cb324---dedeputinolefevuresobu.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/wakage.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=indemnity+clause+examplePDF 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_off0000d415.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD415 10720 bytes
SHA-256: 932bd2ada2de690f0a9bc1bfc6ebc55322bbee21df4a282c8b41e73ce3c3fa01
font_01_sfnt_off0000ecb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB3 18420 bytes
SHA-256: 7dd1df067ea28f44f4e2bef689b79a6729ae97540f8a0922aee38f593f37bd3a
font_02_sfnt_off00011c0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C0F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1