Malicious PDF — malware analysis report

Static analysis result for SHA-256 f84c537534ad78a6…

MALICIOUS

PDF

68.0 KB Created: 2021-09-26 03:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2d22a99fb8f15ebb670da642308c337c SHA-1: 33df71100f034c1d2ce63cc3b56f3100c207138f SHA-256: f84c537534ad78a62b673b11c6556714d34c457aae880df6b6741c6a21cca71d
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF is identified as a phishing lure due to its small size and image-heavy content, typical of a screenshot designed to hide a clickable link. The presence of numerous external URIs, many hosted on potentially disposable domains, further supports this. ClamAV and ML classifiers also flagged this PDF as malicious, indicating a high likelihood of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://masterkontroll.hu/ckfinder/userfiles/files/resut.pdf In PDF document text
    • http://szentimresiklos.hu/upload/file/25490873208.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/19352021532.pdfIn PDF document text
    • https://indreninepal.org/userfiles/file/sopakafatazugajutep.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/xofifabedasibotaxutorud.pdfIn PDF document text
    • http://xingyeknitting.com/userfiles/files/18865790176.pdfIn PDF document text
    • http://wronba.com/uploads/wysiwyg/file/luguzib.pdfIn PDF document text
    • https://servicio-mexico.com/images/file/95139033363.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021917156311041.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613078842724e---xezorizixujawunegafujiteb.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/defimu.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/vokuvorenufu.pdfIn PDF document text
    • https://tidaksusah.com/contents/files/pebobop.pdfIn PDF document text
    • https://nexusmediation.nl/files/vunajirirodujadoxeduroro.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/gerigegikedodibibokoxaga.pdfIn PDF document text
    • https://valstybestarnyba.com/upckfinder/files/95247988058.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202109250555222165.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/22911152854.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/161410e5a3a3ae---94371670357.pdfIn PDF document text
    • https://teamcode.net/upload/files/pofipozatumetiroz.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/48620828707.pdfIn PDF document text
    • https://atiksigorta.com/files/gugizarojovo.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/46625080973.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=beaglebone+black+android+source+codePDF 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_off0000ad62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD62 13860 bytes
SHA-256: b947a406df8e7e0c933d7cd533ad532332e9121de11c034453f5d7f54d452807
font_01_sfnt_off0000cfdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFDB 10832 bytes
SHA-256: be6325db9429339e50f6d7fef4f8e73a776102ccf2f8cafd918d5a7b635a47b0
font_02_sfnt_off0000e8b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1