Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ad7c5cdafc9bf67…

MALICIOUS

PDF

75.6 KB Created: 2021-09-19 16:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ae81cd773627358e0b763894701be93c SHA-1: 5061223eaecb2347e4730787f14798578acb0c17 SHA-256: 7ad7c5cdafc9bf67583d243a7641e2f25cfdbd69a8613ac2070c9af442c7dcb0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics and a machine learning classifier as malicious. It contains numerous embedded URLs, many of which point to disposable hosting and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports this assessment. No scripts were extracted, but the presence of many external URIs indicates the PDF's primary function is to redirect the user to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://nomylo.ru/uplcv?utm_term=aladdin+ep+457 PDF link annotation
    • https://soudurelausiere.ca/upload/editor/file/furax.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132279570435---97599794152.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/58682442565.pdfIn PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/72047287458.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/tojotoraburujitupigefur.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/depokipagobuxumu.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/jomazedobosini.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/nebesadiwezerudumulab.pdfIn PDF document text
    • https://coevent.ru/upload/files/43869212772.pdfIn PDF document text
    • https://smartech.lv/sites/smartech/uploads/documents/files/nexemetefagedim.pdfIn PDF document text
    • http://ortopediaszombathely.hu/editor_up/burisexovin.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/pebivofofowo.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/941c6fce576e75b54c9a0a138d2e7fa9/78887257444.pdfIn PDF document text
    • https://turkeyinsurance.info/images/file/zojeg.pdfIn PDF document text
    • http://synergyproperty.com/images/files/jabiparafukazi.pdfIn PDF document text
    • https://topclassgardening.nl/images/file/64905931697.pdfIn PDF document text
    • http://ktcyy.com/ckfinder/userfiles/files/dugemuzegoludupedefapebex.pdfIn PDF document text
    • http://chinamakina.com/userfiles/file/mikoguba.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/wevoderirodita.pdfIn PDF document text
    • https://shiksha24.com/userfiles/files/bakexufezigotuputi.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/75731327105.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/sivepuradabinafixe.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/72367903364.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_off0000c11b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC11B 18324 bytes
SHA-256: 470585f7ec77d3db98a7ebb2dc2ca250c2cc37a0dfc3e53b7b9dafe9543f1238
font_01_sfnt_off0000f0e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000108fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FD 10140 bytes
SHA-256: a5eab16e867a387af006267b23eafc3475ee5c2f6d66af22bd09850606ce6e93