Malicious PDF — malware analysis report

Static analysis result for SHA-256 917e06f12f18655e…

MALICIOUS

PDF

99.2 KB Created: 2021-07-08 02:35:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 59ac20a085fb561aad8b505e659e988e SHA-1: 605a8ad6dacff40591495fe3ca8f84ebe6b00134 SHA-256: 917e06f12f18655ef125b92d367fc5247cdc75e43128e51c0f4141c59ad57448
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to domains that are either compromised (e.g., using WordPress upload storage) or appear disposable. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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 https://limblength-sldf.com/userfiles/file/vodexuwom.pdf In PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/u1lk195ssf6bi4fu9k2dqhkvi1/6662130558.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/tabenemegubitikugoro.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097d1d94ebd4---1221510128.pdfIn PDF document text
    • http://gialtour.it/themes/userfiles//files/kubipiforasoxofajevosiwur.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/mudikebibuxagupukesojil.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/48c7d18e3ddfed5bb9c9f3af8894f92f/45367013876.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/69365842313.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/6a9614edded8a8ad50eaad66b551a2b4/vexobovulovogoxowobowetu.pdfIn PDF document text
    • http://cdmatik.com/uploads/file/pusofodizo.pdfIn PDF document text
    • http://interface-referencement.com/userfiles/file/61531118748.pdfIn PDF document text
    • http://sunnysidehighschoolclassof59.com/clients/867562/File/88016264171.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/92434199315.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/c450c607d708b185afc38dd55a5346a6/rozipe.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/b1ade046deb2a70880b6b777c8e39da9/18620786300.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b783ec1554e---60666706191.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/53763364279.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/garisisolubidexowafuje.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080992645f9a---gamimaloxasuronarekos.pdfIn PDF document text
    • http://newfieldclassof1982.com/clients/6/69/69e49ffade321d977af769e13f9f004b/File/7987093728.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160baaef6ad3fb---75070214343.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b390c043c3---76060015382.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/a8dk3bi1l8dutaqk153sd4hpnv/zulafemejagefidaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=what+kind+of+woman+does+a+pisces+man+likePDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/836425689ce0fce7499c033bec2efe42/loxiw.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_off000120aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120AA 17360 bytes
SHA-256: 1608d6b2ea7db27e13f81dce537a24ea9b7ddcae022110e95e712ec08ef4ed74
font_01_sfnt_off00014e17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001662e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1662E 10956 bytes
SHA-256: ad690ce3d7067fe1d479fa782a36a61a34194ca146242bc2ee3d33fd0dee7810