Malicious PDF — malware analysis report

Static analysis result for SHA-256 3218d0ac9f89b890…

MALICIOUS

PDF

83.8 KB Created: 2021-08-19 05:24:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 32ed83ee4044154fe452ca0efcaed3a7 SHA-1: c678ab7d36899a78d53ab3f4146532f23aa4ccdf SHA-256: 3218d0ac9f89b89076fedc4f3c0c8525a0d2c7a23694d834f83a9b16ffa02bd8
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, including one flagged as a random URL and another part of a link farm on disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://nomylo.ru/uplcv?utm_term=ejercicios+resueltos+de+notaci%C3%B3n+cient%C3%ADfica+suma+resta+multiplicaci%C3%B3n+y+divisi%C3%B3n PDF link annotation
    • http://slsnn.ru/content/file/bidexuvorusetobagagizaz.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/limafokivaw.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/25273afc51fd174708b27ae5b5486763/97281310994.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/95296955409.pdfIn PDF document text
    • http://rheinmotel.com/userfiles/file/52117706772.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/bopufivin.pdfIn PDF document text
    • http://unseenadventure.com/userfiles/file/19286532586.pdfIn PDF document text
    • https://sealordhotels.com/ckfinder/userfiles/files/94506326310.pdfIn PDF document text
    • http://majesticcaliberenglishlabradors.com/clients/a/a7/a77fae3751d16767b5fd1969bdae34dd/File/46091560414.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/jasorojilolitujajoziwosag.pdfIn PDF document text
    • https://unibel.pl/pliki/upload/file/lenumadewonipega.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac86eb17945---47638350679.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/kiditabokasibegizabazora.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/vimuna.pdfIn PDF document text
    • http://qianlong99.org/ckfinder/userfiles/files/14194999041.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/35903796244.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/17088901410.pdfIn PDF document text
    • http://chenruichem.com/upload/files/79403742788.pdfIn PDF document text
    • http://lowchens.org/userfiles/file/tufodizu.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/wejokamipurotufaxusasi.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/23968006812.pdfIn PDF document text
    • http://xenangheli.vn/public/files/bifazupab.pdfIn PDF document text
    • http://anvlaw.com/userfiles/file/47030065151.pdfIn PDF document text
    • 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_off0000dbb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB8 18160 bytes
SHA-256: a05b7ce791147e85bd79b0c5e3885ccca8303b5856013dbd43e4afcbc8a63765
font_01_sfnt_off000109be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109BE 11372 bytes
SHA-256: d7e7a5de9a2512301ca1c6246d025d7cf9b41bb8faf33107ef2cb41ccdf21e17
font_02_sfnt_off0001243a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1243A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1