Malicious PDF — malware analysis report

Static analysis result for SHA-256 90d8183a80956d06…

MALICIOUS

PDF

105.0 KB Created: 2021-09-05 11:10:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a29007b336e35d856f9d48f164a64b29 SHA-1: 5bb381fb1192762c8d7549c05657d478e307700a SHA-256: 90d8183a80956d06dec00275922f96639f65ca7518bf61fe65c71b650ea65cdc
96 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the presence of external URI heuristics further supports its malicious nature. The document body is heavily obfuscated and appears to be non-readable content, suggesting it's not intended for user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 5

  • 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 https://crysiq.ru/uplcv?utm_term=the+meditations+of+marcus+aurelius+antoninus+pdf PDF link annotation
    • https://telechips.com/ckfinder/userfiles/files/mulazirokuwiwenunupexamev.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea4a4d9af9---98777922324.pdfIn PDF document text
    • http://bong-dem-long.org/upload/editor/files/98272129515.pdfIn PDF document text
    • https://capecoralliving.com/media/file/jekavapapitibumodivizuw.pdfIn PDF document text
    • https://drlanda.hu/user/file/68831802327.pdfIn PDF document text
    • http://fullx.net/files/zipalemupipopikuridivuz.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16099b872a8052---kuvawafumi.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eca973c05d7---38974162642.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16094589241c34---65062896880.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/nefigimujetufugerag.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/c050b523824947cb68d0cb6bbf0d58a9/23363423758.pdfIn PDF document text
    • http://geopraxis.it/userfiles/files/jibuworagijipoj.pdfIn PDF document text
    • http://gandolfiarchitetti.com/userfiles/files/bivata.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/51477431999.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/902f87535dc18490481596fa52d14028/11385337067.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec428257b25---dasizonasek.pdfIn PDF document text
    • http://chicohigh1987.com/clients/47015/File/kupezixadufuketo.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/zolejozaxixopum.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607750c15e212---zefakomepivan.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160abecde40a1d---94862260728.pdfIn PDF document text
    • https://pachetedeturism.ro/images/files/13250203034.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/jabokubebalamixavewizediv.pdfIn PDF document text
    • https://mp2020.csysadmin.com/ckfinder/userfiles/files/98738508452.pdfIn PDF document text
    • 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_off00012c3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C3A 21488 bytes
SHA-256: e01ba03eaf746149dca3e0ddd61243fd8a87262fa3952ab7a04108d36f15c733
font_01_sfnt_off0001649d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1649D 10948 bytes
SHA-256: b336255934fd25231a3d063bb4f4304d552dcab1f73b57d2063b7604e912bf04
font_02_sfnt_off00017dd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17DD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1