Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cf3fbd4f07d729c…

MALICIOUS

PDF

91.4 KB Created: 2021-08-31 01:33:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 8465e9c19887cfa07f35e89055ec8217 SHA-1: a7b522ef9575ca8fbf994b2ef3705808ab010f6e SHA-256: 3cf3fbd4f07d729c9ad421e3dad2ece30cee6342e8f437e7d90543706d3c9c85
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various websites, many of which appear to be hosted on compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of multiple link farm heuristics reinforces the attack pattern of directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://vientangluc.com/upload/files/lukesonud.pdf In PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/78382188920.pdfIn PDF document text
    • http://gabortech.comadmin/file/85766727137.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/61534696739.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/21235433371.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3243dce54---nubimaxibemogipoxiboju.pdfIn PDF document text
    • http://somersetcountybar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gugasanidukuton.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/55779389442.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e7794d13618---58942821838.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160844cef85197---62421677420.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca0571385a1---jonaxikagipo.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160afca0e3c3bb---kutawikuretepujek.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160806f2574e9c---48235129776.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/3cvvpjop7l4flk1kbbbpltfofd/25797060935.pdfIn PDF document text
    • https://apronorte.org.br/ckfinder/userfiles/files/78598115726.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/sifijisixozirudutoradiz.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/d219f47e459fefaf3783504075c8f41b/68883827499.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/91471885736.pdfIn PDF document text
    • http://nomorecpapmachine.com/userfiles/files/fevipobula.pdfIn PDF document text
    • https://agrimal.pl/userfiles/file/55170060183.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/d821028b2359e24ce5793a146a1bc71b/26279498095.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc708b4e03---kotuvizogevuterojaxibebu.pdfIn PDF document text
    • http://baggiez.net/userfiles/file/wovigavegokopujebibe.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/sekonuvaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=stick+in+englishPDF 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_off0000f4df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4DF 22912 bytes
SHA-256: 050fa02bab2419b3af760da655b119e11d16c6d9d247b44297e1dd36bd85dfd8
font_01_sfnt_off000130b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000148cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148CB 10292 bytes
SHA-256: 9c047dd0bc0b20b6fff9369c7063a10d4e69a9d7d5d596505c84920cc6cb86ea