Malicious PDF — malware analysis report

Static analysis result for SHA-256 db4a1ddd06aeee39…

MALICIOUS

PDF

82.0 KB Created: 2021-08-29 12:03:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8e549c3b5774ec1591b5f31bc0b5469a SHA-1: e870414b33a98a1b6e1859bdbef18ef8359244ed SHA-256: db4a1ddd06aeee39ccfe2eb9afa1c1dcb5a40c6c6f7648a526fd001233464ed1
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, characteristic of a link farm designed to mislead users. The presence of these links suggests the document's primary purpose is to redirect users to potentially harmful websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://yuha.be/_files/file/86824386299.pdf In PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/38234377157.pdfIn PDF document text
    • http://aktifbant.com/resimler/files/91688837178.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/nuvukedizavopuzegosilo.pdfIn PDF document text
    • https://hsdinstruments.nl/uploads/files/63853793913.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c549841c79f---nozutabewokamu.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/bifurosabiperumode.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/megugaragupudebuvuv.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b58f5e48f2d---majusuf.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/puzenofati.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/545b51a087d073f4f8f4e0c50ad0f0ec/vobetixagoj.pdfIn PDF document text
    • https://z87992961.com/upload/files/20210821095138.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5671f66da5---10131107611.pdfIn PDF document text
    • http://blackivy.pl/userfiles/file/53805601491.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/9a7ro7vu44a38tbukmbr04dbmj/xadisutewap.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160724338cf8a1---95749585458.pdfIn PDF document text
    • http://legendtec-eg.com/wp-content/plugins/super-forms/uploads/php/files/1u80fh37mvaqd2a8mpcl34eks0/4267360255.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/0a51209a51439aead9528232137ab5c4/22285401739.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612749b4a74bb---fumenekugexijonivirasi.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/58955394540d9cc67dcfd8dd5baec93d/gaxudekesevizaxapoduwe.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f61e1af8c---89047674483.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/cff2c2852755e7dda3588b51abe53273/27112837835.pdfIn PDF document text
    • http://55thocscompany.com/clients/62662/File/fofirirefevadisonemuregej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=maximum+number+of+absences+in+high+schoolPDF 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_off0000dd1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD1B 16656 bytes
SHA-256: 29af5e1565c350866201746679cd403876c4925ca0f8c6044a5c32b29c8484ba
font_01_sfnt_off000107e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF8 11020 bytes
SHA-256: 6ea5cae73335f724dc25c55e9631eb3628efdfa863821941f10b4e57b1252d30