Malicious PDF — malware analysis report

Static analysis result for SHA-256 917997fde2705182…

MALICIOUS

PDF

77.0 KB Created: 2021-09-01 11:54:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bf753efef712bd98d00e0cd7e55587fa SHA-1: 4131127d2a68ca654689a8416d0844b54a919f47 SHA-256: 917997fde2705182b1ee673435c3ab41289e3c570fc6d13ce8a380481cc42a27
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm hosted on compromised WordPress sites. The PDF contains numerous URLs, many pointing to potentially compromised upload directories, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e64c6ca647---revagibidadugudotejonux.pdf In PDF document text
    • https://club-sports.net/uploads/products/files/6427762092.pdfIn PDF document text
    • http://shsalumniauditorium.org/clients/f/fa/fa32e32112b7cad64a7d7e78b95ed61b/File/wuparerafepusirosuxu.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/18d5481960fd4500690ef9dd9fda60e7/notipivizujugubifeb.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b93d61dbbe---30697846847.pdfIn PDF document text
    • http://songhungthuan.com/upload/files/liveselixoretika.pdfIn PDF document text
    • http://www.nagsa.es/ckfinder/userfiles/files/40674481711.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/93071180180.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f28023b1528---84314550884.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/zufunewimelapuzo.pdfIn PDF document text
    • http://nfc.soo.jp/file/vivimujuloduwibalexexot.pdfIn PDF document text
    • https://firsatpin.com/calisma2/files/uploads/10843811321.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16087da4895d61---69440500769.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6452ad646f---48273977628.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7e63c306e---puseranevupiv.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160e9004749714---dupepukijinugomapomovulug.pdfIn PDF document text
    • http://okuninka-biale.pl/userfiles/file/8068223463.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16087214e16a85---sijegubifinesu.pdfIn PDF document text
    • http://lmyc.net/clients/875386/File/86271004551.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/215ec427cf08eadd51b3d157db197dec/gewuridujenakimajizam.pdfIn PDF document text
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f93d0d04e2---89025413653.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d5fcd4f2fd0---33717184191.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/f37h45d2to4tvub8mjsjl8bk6m/gupofineremeb.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/f8c3ba1ef8a5e67fa52349db6caa516a/gamukanudopomowugusokabiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=itchy+scratchy+throatPDF 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_off0000ced3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCED3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e6ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6EA 10016 bytes
SHA-256: e33635c4658b656307b72a78758308c438fa7dee35b29ca620d209500ec71a4d
font_02_sfnt_off0000fd54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD54 16316 bytes
SHA-256: ddfd51e3629d719485d7506460ca4eda8a409b26790f3bbca891834b91e8c04f