Malicious PDF — malware analysis report

Static analysis result for SHA-256 ade23bb991c9fd01…

MALICIOUS

PDF

75.9 KB Created: 2021-09-15 15:30:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9f19927356650d1775169ed21f13a088 SHA-1: d84d1f1537e14d416b83c5302b0b9ab2d1a29fdd SHA-256: ade23bb991c9fd0138b1788fa173f48f15febdb1e9ac8a747adfc80281af27e4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs pointing to disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the use of embedded JavaScript for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://crewmak.ru/uplcv?utm_term=pokemon+fire+red+download+mega PDF link annotation
    • https://hnhaa.com/userfiles/tnejp/files/pimomuweka.pdfIn PDF document text
    • http://firesecurity.sk/userfiles/file/terapekon.pdfIn PDF document text
    • http://skolky.info/foto/images/file/sudurajeburujiwof.pdfIn PDF document text
    • http://oguzlarotomatiksanziman.com/depo/sayfaresim/file/gefaxediv.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/dofenadeta.pdfIn PDF document text
    • https://thieumaunao.vn/workspace/develop/uploads/ck_upload/files/dogurozeji.pdfIn PDF document text
    • https://xosobacninh.vn/webroot/img/files/44591664984.pdfIn PDF document text
    • https://vestol.bg/files/file/tiseder.pdfIn PDF document text
    • http://nordicwalkingturak.hu/_user/file/fovivazumito.pdfIn PDF document text
    • http://4bx.pl/public/file/nemakozafepotapovijamudu.pdfIn PDF document text
    • http://hotelbasantresidency.com/uploads/5874103770.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/jutamozejadudatufume.pdfIn PDF document text
    • https://mclandpin.com/calisma2/files/uploads/luwakefisod.pdfIn PDF document text
    • http://duonglaohanoi.com/userfiles/file/96639187618.pdfIn PDF document text
    • https://adtw1.com/ckfinder/userfiles/files/85855113377.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141cf294dff0---10405706671.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/85699798698.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/34775659366.pdfIn PDF document text
    • http://melodylavernebettencourt.com/media/file/takeka.pdfIn PDF document text
    • http://srtprogetti.eu/userfiles/files/315493932.pdfIn PDF document text
    • https://fasaac.org/temp/files/zorapasa.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/2889507756.pdfIn PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/5971610084.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/gumakabiveb.pdfIn PDF document text
    • https://scalping.ir/data/files/file/77319712055.pdfIn PDF document text
    • http://francescasciortino.it/userfiles/files/vojesip.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_off0000c2af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2AF 17980 bytes
SHA-256: a5d2c667039d36eea768e535cff9c6aac734735abd46a7f8094cda04a786f0f5
font_01_sfnt_off0000f139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF139 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010950.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10950 10612 bytes
SHA-256: 1e27926b5eaba7b0d045eca1d28cf31cdf841aba35fda7c0f9771d26497c2cbd