Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ff2924277532f54…

MALICIOUS

PDF

78.6 KB Created: 2021-09-13 14:56:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7f65812577a61665a87d5ada86f05c0f SHA-1: e26ccffc4605e6de4c408fe74090b8f3af1fe786 SHA-256: 8ff2924277532f549c83061b71e63dbd0d37fc295b4fcffee52e46eb252f23e9
96 Risk Score

Malware Insights

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

The PDF file was identified as malicious by an ML classifier and contains numerous embedded URLs. Several heuristics indicate it functions as a link farm, with many links pointing to disposable hosting or compromised CMS upload directories. The document body is unreadable, but the presence of a link farm strongly suggests an intent to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 http://studiodispirito.it/userfiles/file/51757127926.pdf
    • http://dytac.hk/userfiles/buwimaravaviwugeginorep.pdf
    • http://rent-lease-no1.com/userfiles/file/20210913020343.pdf
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/busokamiwumem.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef4a39597b---sorafejukarivukafu.pdf
    • http://redemaisfarma.com/userfiles/file/69185743533.pdf
    • http://cen7dias.es/userfiles/files/fotivaji.pdf
    • https://self-storage.sg/images/uploadedimages/file/kowadipopikoniki.pdf
    • http://benthanhsgfarm.com/images/uploads/files/75653439729.pdf
    • http://cnokorea.com/userfiles/file/dapijasategegumara.pdf
    • http://dija.lv/public/userfiles/file/91900025923.pdf
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b0ae84cde---58839311941.pdf
    • http://tz5168.com/uploadfile/image/2021/09/02/file/20210902_030825_194.pdf
    • http://thibidi.vinadesign.info/uploads/images/files/zixatagijopewusinaresasa.pdf
    • http://klick-tipp.info/ckfinder/userfiles/publics/files/migiwupibefuvofasizu.pdf
    • https://elemental-ia.com/userfiles/file/veler.pdf
    • https://dodatkireklamowe.pl/web/uploads/files/kotuvamelaxasega.pdf
    • https://zlato-stribro-investice.com/upload/files/75248540536.pdf
    • https://gamepinleri.net/calisma2/files/uploads/namifo.pdf
    • http://meble-tk.pl/userfiles/file/46132154178.pdf
    • http://twozonechickenlasvegas.com/uploads/files/xuzebeweb.pdf
    • http://kondicionery-vidnoe.ru/upload_picture/file/xujitakati.pdf
    • http://yjbiotech.cn/upload/files/60039830011.pdf
    • http://nieruchomosci-swidnica.pl/userfiles/file/buwototazomisinu.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/db9d343c75a64104a02bc1baf641487e/todarokunujoberogedamivi.pdf
    • http://boki.hu/editor_up/viwupiviwelu.pdf
    • https://jkmart.net/FCKFiles/File/11275382732.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=om+symbol+copy+paste
    • 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_off0000c686.bin
5f74135e2793701d6bf5ca608f842906638cadd7a11c5568185596cf97d968cc
pdf-font-stream PDF embedded font (sfnt) at offset 0xC686 10520 bytes
font_01_sfnt_off0000de64.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE64 16792 bytes
font_02_sfnt_off0000f676.bin
4996389702d032e42f6a5db399babd3a041714480ba5ac692db645cc43466936
pdf-font-stream PDF embedded font (sfnt) at offset 0xF676 20360 bytes