Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cb605e1ade3bbcd…

MALICIOUS

PDF

86.2 KB Created: 2021-06-28 14:13:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8634602f0671f9089bf2ff5dbd61832f SHA-1: 4a21eefa93cb7c1a112dfc3ab600315f2ffb6b28 SHA-256: 3cb605e1ade3bbcd60a0188f9a11127291aef05fc06a15ba75e2885dbfed962d
176 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, and it impersonates a document signing service like DocuSign. It contains a link farm pointing to various PDF files hosted on potentially compromised websites, suggesting a phishing or malware distribution attempt. The presence of numerous external URIs and the overall structure indicate a lure to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • 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.
  • Document signing service impersonation lure medium SE_DOCUSIGN_LURE
    Document impersonates DocuSign, Adobe Sign, or a similar signing service in a signing-request context
  • 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://parkhigh65.com/clients/4970/File/vidudajutisupofa.pdf
    • https://negaratoto.com/contents//files/38726084182.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/6su8egsmehqmijfrtloclke7i3/memomofobosagogetisi.pdf
    • http://gingerbreadvillage.org/clients/e/e3/e396b250b60561adcb946853f9f62e29/File/lemefevezegijawuso.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/irk0m1jhpf43884va6ulal2iqm/magim.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d5d1a9eae---bujopon.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/13975814051.pdf
    • http://tsg-edinstvo.ru/userfiles/file/50605447136.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/04a1ed25fcffkuil2nuac3dmcq/sujuxebojegafevaxix.pdf
    • http://absolutelyneon.com/userfiles/file/72413986320.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608793b4934e9---44043960455.pdf
    • http://ghioroiu.ro/sites/default/files/file/puzireduxutujidunezap.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082a6a4a0329---75990657515.pdf
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/c6d6759696fdddd9f04ccab13d10d436/42349814541.pdf
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/093f2c671fa703bc2fbff6c64f24aef3/76481735835.pdf
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/wekafamufovubuluv.pdf
    • https://recapress.com/ckfinder/userfiles/files/69873263847.pdf
    • http://ridendo.cz/files/file/60758906964.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/62ba3efd3a9120865e681a4f09751589/vupamegosekuj.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606efa9021f04---zexofujepulosevizefeteso.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/4975a76e5015bebbb092eb4f88c4ea9f/kitikikuzopuf.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c7ae925d2eb---10022886987.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/affbaff5742372a874f73626e22b9daa/wakipaluvalur.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=how+to+make+fillable+pdfs
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6b9.bin
2b1a5cc62ffff692feac4bd91d63c6fa73ce9dd57fc6f77bf1bc9715a87cb744
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B9 19816 bytes
font_01_sfnt_off00011971.bin
97abe3ac18b4b4d1ec5e33a4828bee09b0962b0d96a6c55913a0a009fbbca4b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11971 10764 bytes
font_02_sfnt_off00013205.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13205 16792 bytes