Malicious PDF — malware analysis report

Static analysis result for SHA-256 d71089dbfd0b111b…

MALICIOUS

PDF

74.3 KB Created: 2021-09-10 14:24:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8a69ea533c29be87f562781d40b7a5be SHA-1: 2668b345da2fdbbabf39087f31b4905ea59af77e SHA-256: d71089dbfd0b111b03d1d6ebd45766b213abf9e927157ce913519dce2e1ca927
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm and a potential phishing or malware distribution point. It contains numerous embedded URLs pointing to various domains, many of which are hosted on compromised or disposable infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://www.maderas-navarro.com/ckfinder/userfiles/files/gutap.pdf In PDF document text
    • http://ever-pioneer.com/upload/files/58315859989.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/7303658975.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/p33aqkrh9kp5q8gh20ejl2c754/moledejowadokijowuvegake.pdfIn PDF document text
    • http://www.jasolasia.com/image/upload/File/fisiduzuvinepum.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fc6aa1f8619bd56c0ccd4dd0e567bb11/64162868640.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/4108306413.pdfIn PDF document text
    • http://cephedanismani.com/images/pages/file/gilexadiloboniguguni.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/jomewenagukupimew.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/4504741936.pdfIn PDF document text
    • https://www.mtiwelding.co.uk/admin/ckfinder/userfiles/files/36082622397.pdfIn PDF document text
    • https://konteshamamotu.com/userfiles/file/50928051491.pdfIn PDF document text
    • https://elearning-chemistry.ro/userfiles/file/kofugewifewavolofixolelu.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/48782244007.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202109100006208723.pdfIn PDF document text
    • http://www.colormotion.cz/UserFiles/file/20007156756.pdfIn PDF document text
    • https://zahrek.com/userfiles/file/26660926487.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/486b3a783ee5fc542c5d919dae014fa3/kavirigireki.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/lowizejukapot.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4b092ae90---51655374776.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/rirosutolu.pdfIn PDF document text
    • https://samsungklimalar.com/upload/ckfinder/files/28775029508.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/55238096793.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=how+to+reveal+hidden+apps+on+androidPDF 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_off0000bea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEA8 17360 bytes
SHA-256: 763c9a393ad2b2188de67537c69a58e890cc46815c98ccb719ad3e087be4c940
font_01_sfnt_off0000eb2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2A 10632 bytes
SHA-256: d903709df5d467a4333ee8ef9fd01cbca2b84fb0616368684747edcb286df29f
font_02_sfnt_off0001036a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1036A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1