Malicious PDF — malware analysis report

Static analysis result for SHA-256 603643cfbb69a6b0…

MALICIOUS

PDF

113.8 KB Created: 2021-06-29 12:17:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: c3d932191b6aa50f1fea6bfefc07140b SHA-1: 3638d3f9e57542e5d46f4fc69b7a29f365a8bdc6 SHA-256: 603643cfbb69a6b0af57fd01aca89142acc8254e14b8db1286b2c735a03a3202
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting a link farm or phishing campaign. The presence of embedded URLs and the PDF structure itself point towards an attempt to redirect users to malicious content, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9886

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://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608e59ee52f6d---86992836250.pdf In PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c73b5b5f43---34545166070.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b880ca7f8fb---judivusogubokatalalawud.pdfIn PDF document text
    • http://csptech.net/admin/userfiles/file/vurojir.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/620f3d05a73caa8fabbdac65da1097b2/58715391099.pdfIn PDF document text
    • http://laptopcuhaiphong.vn/upload/files/69727907720.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a41fba2bedc---29554500193.pdfIn PDF document text
    • https://uleiuri.ro/userfiles/file/nuxizij.pdfIn PDF document text
    • https://acryl-bg.com/userfiles/file/21521602212.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afc3b73275b---88776635843.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a316ee9128c---metone.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/4d47cff730b8cd9fe7e6cce49ee8dd42/goparixilijiluroxoz.pdfIn PDF document text
    • http://tremonttemplemacon.com/clients/862779/File/34966999464.pdfIn PDF document text
    • https://ayurvedaemart.com/uploads/file/30487392665.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a5db9837a2a---27559708389.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16089caaa3584c---19206635397.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/0dac4a96fcc8dda5ade7d9fbffc86a79/milajelirozudeso.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/a26e465d902c49f8f1a6b2a6ffd3048c/tekafej.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0724cf8d255b088bf592b3da9ac050dd/67262864609.pdfIn PDF document text
    • http://haniltm.kr/upfiles/editor/files/vujod.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/d7d419dc4b8b0857527820bf8d520abe/76172210714.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/33rne7oshcmqkra7p4t19r63s3/73333161888.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608569bf1938a---38231470487.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/1dec4d3f75da0a7fe39da7c00770322a/sekewubajurasuziposesowaw.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1609914ec013b7---75135401065.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/d6037682bd7eadb0bf89be6c71867f91/satozoxaniresatumame.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=oil+painting+secrets+from+a+master+pdfPDF 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_off00015630.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15630 19352 bytes
SHA-256: 0da40a0e97eb0dcdfe1a35cf3952cdd5ae394e3f80dee86e1087af2e29bcdaf2
font_01_sfnt_off0001883b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1883B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001a052.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A052 10988 bytes
SHA-256: b4219827ee789747c650b07d3ab1e60eb8afedea875a60109e3553ca391dfa3d