Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc5873526e4ef62c…

MALICIOUS

PDF

90.6 KB Created: 2021-07-03 18:30:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4a60abb161ee3ddb2b17837254cd591c SHA-1: 1dbaee09592895a0760df9706abe01e8233c34bf SHA-256: fc5873526e4ef62ccc90eb442c96b65d2749d89368da99c9049eaa0cf207103c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to distribute malicious content. The 'SE_INVOICE_LURE' heuristic indicates the document's content is likely a fake invoice or payment request to trick users into clicking these links. ClamAV detection and ML classification further confirm its malicious nature, likely as a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aafee96afa8---pabaxo.pdf
    • http://shepardfarm.com/clients/877021/File/pexoso.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a14fccc0336---bevajojomukewitamexawa.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c4a800bac01---giwoxanozewemasebu.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/diaf38atsaspovpmgqac3792cr/pabajur.pdf
    • https://vokalensemble-vocembalo.ch/userfiles/file/mogab.pdf
    • http://sobsai.com/ckfinder/userfiles/files/12923152803.pdf
    • http://akgikorea.com/file_upload/fck_upfile/file/27483317447.pdf
    • https://widepolymers.com/userfiles/file/51350136242.pdf
    • http://eltonltd.ru/sites/default/files/uploads/32697241780.pdf
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/aaff833c70c82a1c06be43be2f8787cb/26246887735.pdf
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/f4c9c2cf8ae2cb8329ba7179329cff4c/forarepuma.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160b713306e02e---favelujukimoximedova.pdf
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/af1f5d32921ebf2a0032c795d78e65af/xomufoxorenaretoxolo.pdf
    • https://lasvegasrebath.com/wp-content/plugins/super-forms/uploads/php/files/87031167370f8d697c3ce427c1a2adc0/98992393699.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609297593ae72---37881326598.pdf
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/3u2hmop0ucde6ifbl85ddhlbo9/8243905033.pdf
    • http://pspectr.ru/userfiles/file/74471371579.pdf
    • http://beautybybelief.com/admin/images/file/xenusenusajiforixa.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607742d1ba501---fogupakowerux.pdf
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/f6ee422d443649ced16714babef794e9/30150964598.pdf
    • http://kusadasidentalclinic.com/img/userfiles/files/zatikise.pdf
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/k6974d9ucm9v52o4shdtq5u6ts/3118515704.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=contra+between+payables+and+receivables+ledger
    • 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_off0000fd24.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD24 16792 bytes
font_01_sfnt_off00011536.bin
553ba72ab4ff837caea804a878607aab0ad7c3ad5e9344b8708fa1071aaad2aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x11536 17436 bytes
font_02_sfnt_off00014334.bin
6f74065ce977645e17a6460dd3898f95979b04e50ad0965e20e9f020ce54ce5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x14334 11128 bytes