Malicious PDF — malware analysis report

Static analysis result for SHA-256 15915c111cfe0cf3…

MALICIOUS

PDF

87.0 KB Created: 2021-06-30 19:47:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 52e1a8ba6884b746a0b507bb89c3a516 SHA-1: 0e4f0022794e48f837ccc9f762cd38613f0e2ea6 SHA-256: 15915c111cfe0cf33996abaeced38fb0d1c9064f21b3eef7f523f894851fa35f
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and links to compromised WordPress upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure points to a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://coretry.ru/uplcv?utm_term=itchy+laparoscopic+incisions
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/2bmme1o3o8glh77k4ptevfpn5n/38495318612.pdf
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/1018369921ac7c4da1ddec69aec429da/4138317101.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b17349214e---todirowutejanunozilodifar.pdf
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/82982ea2841ac52b9eb149432b59f0d6/dobiwolamoxewesivimorukek.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca801b1f59---83883822728.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/e09643973045532c070f7506ecb94eed/96360703530.pdf
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/ov36alvk4c9uc52kis5if0u8va/tiwutazuguvaderewiza.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/915e8d383fdea58215be14bf2d7d033a/vixuwelotaganali.pdf
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea9072af06---82202496287.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16090456401089---wexefonabixajuvu.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609c0f8dc24fd---72883728731.pdf
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/c13952ba0c6608545a1304a631d8992a/binutobide.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160704f6aa53a7---zuvuxejedexevezemo.pdf
    • http://aweibel.com/Photo/file/93165745781.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e191d498d5---28098694107.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160720148197fe.pdf
    • https://dailyhondaotomientay.com/upload/files/sejikajifemezexofuloziri.pdf
    • https://agrilaui.com/userfiles/file/tosexuluxuxewix.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/3a23717b8385cd73736b683898d0d71b/43508213638.pdf
    • http://cdmatik.com/uploads/file/wifanolom.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16075489f5d9dc---64945640142.pdf
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/qmpis3k6k9aal2hlq8rqrni67d/45671560287.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f9b523fe9---jitepa.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606e1064bdc49---52990089091.pdf
    • 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_off0000f400.bin
ca911401a6ba6e6b98c9570a2a382d1f5df7c5c238b62d5ec4c1f4fedec33480
pdf-font-stream PDF embedded font (sfnt) at offset 0xF400 10404 bytes
font_01_sfnt_off00010b8d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B8D 16792 bytes
font_02_sfnt_off0001239f.bin
75983c370689fea562b94cf6106d0e03e8b3ed830250646aff3bf64f733c8dc8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1239F 16596 bytes