Malicious PDF — malware analysis report

Static analysis result for SHA-256 a11f454f7611bdb8…

MALICIOUS

PDF

83.4 KB Created: 2021-06-27 08:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e2d2bdbc44e4380332e2fc3d491790ac SHA-1: d122e708665a96678f32e9c7465982b6d851ee89 SHA-256: a11f454f7611bdb852fe5f7c248b4a33f2f7e905009637b9547721a1b2a79cb5
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple websites, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/285b566e4dbcbb0b2e6c3d0b2d92ed85/28288623910.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c297f52f7d4---68617170418.pdf
    • https://blsautomation.com/ckfinder/userfiles/files/36947188343.pdf
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160767960c33ef---pujafapetevokap.pdf
    • http://automotiveenergy.cz/userfiles/file/28641433960.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0a85679da---lijig.pdf
    • http://wrhs1967.org/clients/6/61/617565fc8afb9cc6d18abf932d248b7a/File/robono.pdf
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7702d41ec5---mafipiparikirifujulobatol.pdf
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/bpd25ufa6efpam67461lpov4l9/radetaz.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093fbad0af2c---kegaxovepitebupusokivo.pdf
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c445b159b---5733494954.pdf
    • http://abogadosaguilar.com/ckfinder/userfiles/files/gujogis.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b043648c375---zowaxezugofusupimejuk.pdf
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/70dca747ec6eeebde6a387601c1083ce/xisixibupo.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f893f96d64---15841951511.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/gmhajkkqh2km8e0kvp7va1dhl7/jovisefukutozopubupuzemu.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075704bc9a46---vuxobozosetemakesedivir.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/lkquekpdtalplbq20oo1qrj141/tedew.pdf
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8fe5ea9208---xudigipizefimomokojibak.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071143cac212---towopimilesonagiwozarozex.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=dipole+induced+dipole+example
    • 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_off0000e457.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE457 16792 bytes
font_01_sfnt_off0000fc69.bin
ddceaccc2ef3b3a7688ae70ae12bb22d741b9dce7e1a00e1f7f9e8a68da8a6bb
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC69 16960 bytes
font_02_sfnt_off000128ba.bin
dacc67ea2fb314660835a25a45e784a0bec1016467cf79bada48d2cb30907b89
pdf-font-stream PDF embedded font (sfnt) at offset 0x128BA 10512 bytes