Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2b346854d851312…

MALICIOUS

PDF

76.9 KB Created: 2021-10-04 15:35:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f2e3ec61f29b4d2a5ed4d149093d71a8 SHA-1: ca229312981b13fed90101fa0f988f88e2c42586 SHA-256: d2b346854d851312d8c156046a4d4f766c89cc9b2291493db55500e5ae9f93f1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, suggesting a link farm or SEO abuse tactic. The document body is heavily obfuscated, preventing a clear understanding of its direct user-facing content, but the overall structure and heuristic firings indicate a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://wmasgroup.com/userfiles/file/63363115813.pdf In PDF document text
    • https://ietc-oman.saktoon.com/userfiles/files/monexo.pdfIn PDF document text
    • http://hjhchem.com/upload/files/10201421623.pdfIn PDF document text
    • https://volnynaklad.cz/data/file/8401603884.pdfIn PDF document text
    • http://tce.vn/imagesflashupload/file/gojasepap.pdfIn PDF document text
    • http://cellesekorea.com/ckupload/files/wififufidudomewurerat.pdfIn PDF document text
    • http://wirtrauenuns.ch/images/file/23858667289.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/pibezu.pdfIn PDF document text
    • https://csam-villepinte.org/uploads/images/file/sovoputepaxu.pdfIn PDF document text
    • http://seanmore.com/userData/board/file/82640491786.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/93821126005.pdfIn PDF document text
    • http://vanharteyoga.nl/uploads/files/98740903501.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fadea42973---vurilewavowilubanozubi.pdfIn PDF document text
    • http://tatvideo.ru/ckfinder/userfiles/files/semexotomasuzizepupirirom.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/susokejetasolirimebomagon.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/88982734079.pdfIn PDF document text
    • http://dsfly.com/uploads/files/nobobomapaziwisitu.pdfIn PDF document text
    • http://escritacontabilidade.net/fotos/news/file/4151803591.pdfIn PDF document text
    • https://emmaushuis.org/pages/gumikuli.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/kijinubobap.pdfIn PDF document text
    • http://abbeytraining.net/userfiles/file/57324276375.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/temapa.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210909100943.pdfIn PDF document text
    • http://joy05.com/_UploadFile/Images/file/73585475896.pdfIn PDF document text
    • http://commune-bourre.com/userfiles/file/83007727065.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=maiming+meaning+in+teluguPDF 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_off0000c1a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B9 20656 bytes
SHA-256: 175d0cd65379e95c1a401fccd62a4bcd4a6c2a70fd0073180badc5d741202131
font_02_sfnt_off00010fe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE8 10156 bytes
SHA-256: dd3a0bd4eece6a7182b89f352033f138666424cf29791c7df24f87a8323a94fa