Malicious PDF — malware analysis report

Static analysis result for SHA-256 99779066c68f9b39…

MALICIOUS

PDF

83.1 KB Created: 2021-06-25 13:46:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 79c5d1c0bc695efee644c44d73784981 SHA-1: 3c11c4ed51231caff7b0d82f6c834a7bb3e22f60 SHA-256: 99779066c68f9b391beeee70a7d8de9d70ce0edb01335f396f62dd9d8b2ab1af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm used for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to redirect users to malicious external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://perfecthospitals.org/FCKeditor/file/77225121421.pdf
    • http://fullcolorspandoeken.nl/userfiles/file/49029111838.pdf
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1608faab8c58f0---85805500359.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/256923013d214857af4916403efc7e9d/lisovupotenilege.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077d9292f733---83199964696.pdf
    • http://bitite.lv/media/txt/122/file/vomemol.pdf
    • http://cdn.eagle.mn/uploads/userfiles/files/xavomoxuvi.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c675894c1---50829131921.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5fd658d426---tenikowise.pdf
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/72b7e4ad69c829f344a524cf0de94e09/tinajozinunida.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/597b9a1a35e5a82a0031bffe0046049f/pomanegoveb.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f02e382048---tikusofu.pdf
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/lo49v8tdt8l8f6vmah7ggobut2/tuwufewoboviw.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096ce642de01---21328045226.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b46f865accfe9c3a7fe3904d1d4d9b9e/vuvikelomif.pdf
    • http://banghetretruc.com/media/ftp/file/tulipukeno.pdf
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b9a4d8b4c---kevuravusa.pdf
    • https://www.alapan.org/fckimages/file/mosobefujekogewuwakafuvoz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=lily+james+the+tale+of+thomas+burberry
    • 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_off0000de4f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4F 16792 bytes
font_01_sfnt_off0000f661.bin
0a7f0d1602391dba49d3f544cef2ccad7272920ffc15947063da1ce1eca163d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF661 18120 bytes
font_02_sfnt_off000124c4.bin
a35f4eaaccaea45d224d06ef5714d732380c1e7f8c7d508c08d968fb5c7773fd
pdf-font-stream PDF embedded font (sfnt) at offset 0x124C4 10816 bytes