Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4b867cf4b3c3b52…

MALICIOUS

PDF

82.0 KB Created: 2021-08-16 19:48:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: a2f2dc26dfc559982428ce53e0a65822 SHA-1: 31f40309b237ef349ea1aba5e04ce3e34af733c7 SHA-256: d4b867cf4b3c3b52e89409ad8186dde9c503b10b9a76ec335e0185b975aefb65
156 Risk Score

Malware Insights

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

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a phishing or malware distribution campaign. The document body is heavily obfuscated and unreadable, preventing a more detailed analysis of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://iberia-ex.com/images/blog//file/10725318863.pdf In PDF document text
    • https://phoenixturkey.com/upload/ckfinder/files/52048920159.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081809c7b850---wetiwolimife.pdfIn PDF document text
    • https://perfectprojects.ro/userfiles/file/54996463747.pdfIn PDF document text
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/6a99e1648fb110c37af7cc90c7d7cb96/41086153707.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f70a21663b---23636268555.pdfIn PDF document text
    • http://sea-cruise.ru/ckfinder/userfiles/files/zakofitu.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/38f4554d133bb15537a288bcf1bd3d92/13491823180.pdfIn PDF document text
    • http://alliance-ic.ru/uploads/file/nalutodedilikan.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/d6d40654de72ad9b41eccc04f08381c9/rogorewikavebepogof.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/46316166726.pdfIn PDF document text
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/6lsqce75mrnlarilshr3retst6/48732931898.pdfIn PDF document text
    • https://ambient-interier.cz/files/files/lidabaxotite.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b38a5f30e5a---vuxej.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160afac04d8870---88214821054.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/o8cbepehs99019sf0ovpe5sv6m/73046834493.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/dakezasalobuwejujazit.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/82469645890.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/j5fn2t571r4j8ar8b8ogd7861d/pamovajapolafadasex.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/54kufs5fmu94m8mhk811vqvck1/49346731187.pdfIn PDF document text
    • http://3xlove.com/uploadfile/file/rujaxiz.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160a4afa07816c---66232273116.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/62711193645.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210808_3C056E40458A3D85.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/f8ik3m3vlsplkfv16e3tr5ml9d/veniwin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=how+much+does+it+cost+to+check+transmission+fluidPDF 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_off0000dd33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD33 11012 bytes
SHA-256: 935d09f11fd7f10b68831c9ed7b1078fa1a913d4be8bd17e036a25c959511fd3
font_01_sfnt_off0000f6a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010eb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB8 16636 bytes
SHA-256: 22b9434aabd42f2c5d66a52b3beddaa776b3b1bc05fb3e17b35db2abc43e5d64