Malicious PDF — malware analysis report

Static analysis result for SHA-256 58284b3ee6c07314…

MALICIOUS

PDF

79.6 KB Created: 2021-07-01 16:28:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d9e9f3c84b428a8ffe08df3481ed218 SHA-1: ff2618a71cfd177165c54d24e00b8ea9e660953a SHA-256: 58284b3ee6c07314dcbc92754d88c1c7366dfd31716dde2d1986b01de0c7aea5
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, many of which are compromised WordPress upload directories. The document body is heavily obfuscated and appears to be malformed, suggesting it's not intended for human readability but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9d0c2778fc---27254943096.pdf
    • http://highendschmiede.de/highendfiles/file/tagasemege.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160729e4467cfb---81128875799.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3e2e1d7828---58035824262.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0719fa4f16---sonokokawidawup.pdf
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc268a502b---29105718827.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/3kmcr5pjn1shnd6ffbjj6btu15/84630915018.pdf
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607738350e087---20829265262.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/84m8rlv1baugqt7ptfdgc6lje1/fufozugidikokipumazug.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a23e66d18df---modoneror.pdf
    • http://knshzj.com/CKEdit/upload/files/temetezo.pdf
    • http://botosani.ro/img/uploads/file/44200046896.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1607211a87cd09---zuvivad.pdf
    • https://africanresearchcenter.com/userfiles/file/vafilolifadisiti.pdf
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/dbed0bd10bd65df02e7c234f1df33c8b/wikaxezunixiwinotanut.pdf
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607122f4cf381---lesoxevosoninilunu.pdf
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/24fatb7k3c2jsc4dcpeplil16i/dofasikuzaretipukerevasib.pdf
    • http://palazzodiaz.com/userfiles/files/linamanukarexarafesil.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/c008cfe44fcc6acbef9d63efb63ad1d3/tugamolowelatibavokazemo.pdf
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/672nkfmhrf39mrenub2f3g2spa/wawujugoka.pdf
    • https://tonitomov.com/picture/file/3856285219.pdf
    • http://ciaooo.ru/uploades/userfiles/file/75376165311.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d7f3c20ff---vivopozuf.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=4+pounds+12+ounces+in+kg
    • 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_off0000d4a7.bin
aa780ff17c8b7f5697e79c5d044a3304a84a1cab4e5d5fd62fd68e8839412bbf
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A7 16912 bytes
font_01_sfnt_off000100e8.bin
046a7bb02404c59f4c28096a508ea02161f798423386d2394dc92e76ab0f6dea
pdf-font-stream PDF embedded font (sfnt) at offset 0x100E8 10628 bytes
font_02_sfnt_off00011940.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11940 16792 bytes