Malicious PDF — malware analysis report

Static analysis result for SHA-256 53ce2ae1e4233207…

MALICIOUS

PDF

76.4 KB Created: 2021-09-20 21:57:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: a408eac63d0079ea42f74c180162cd23 SHA-1: 3fec84eabb613c8b6855778c2612c5f3f0e11747 SHA-256: 53ce2ae1e423320718bff9aa5c68f746c103c2d82bfe39398f5f0594cb8a8bea
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. The heuristic analysis identified it as a link farm with a high number of distinct hosts, suggesting an attempt to distribute malicious links. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution attempt, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1614367369529f---77179712288.pdf In PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/18979416964.pdfIn PDF document text
    • http://samocvet.org/foto/ck/files/75824244349.pdfIn PDF document text
    • http://druckmaschinenservice.com/uploads/fce/files/gedonotutolaririnitu.pdfIn PDF document text
    • http://lachina.cn/upload/file/19945028015.pdfIn PDF document text
    • http://compsult.net/userfiles/file/88234729425.pdfIn PDF document text
    • http://allier-genealogie.org/File:/rujozuzebetewapewafas.pdfIn PDF document text
    • http://balbu.hu/uploads/news/file/32222248299.pdfIn PDF document text
    • http://scbczy.cn/up_files/file/20210918_035211.pdfIn PDF document text
    • https://n-vv.dk/userfiles/file/wiwijisete.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021091207353667.pdfIn PDF document text
    • http://seychelles-resort.com/images/blog/file/widevinutober.pdfIn PDF document text
    • http://vntattoosupply.net/uploads/image/files/boripefiromu.pdfIn PDF document text
    • http://kayapalinakliyat.com/file/95310502622.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/xapewixag.pdfIn PDF document text
    • http://yonseri.org/userfiles/files/80028388327.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/fuvuwum.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/44777832050.pdfIn PDF document text
    • http://griesvoegwerken.nl/UserFiles/file/299752903.pdfIn PDF document text
    • https://foundationkuzmanov.com/files/85179679645.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/83137743648.pdfIn PDF document text
    • https://doublehaircenter.com/upload/ckfinder/files/fidivegudewimoxosawuv.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/9858ec41c79bf9335fd1744fe38ede67/jefibe.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/vasore.pdfIn PDF document text
    • http://ahzgbh.news-read.com/upload/files/lovixitowipufi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=dc+zack+snyder+justice+leaguePDF 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_off0000c42f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC42F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC41 17872 bytes
SHA-256: ad6f397fef642be2f755e112b5341fc91ecaea92785156e2b3f47e9c75ca57a7
font_02_sfnt_off00010a9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9D 10920 bytes
SHA-256: 28c33eea3a34d1011627f45e71ef07965b06cbd93ed969634d0a97a1eec47e6e