Malicious PDF — malware analysis report

Static analysis result for SHA-256 104e9b55ec919cce…

MALICIOUS

PDF

87.4 KB Created: 2021-09-18 16:43:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5207cb2fcfa848dabd2c325b2e7b4fbf SHA-1: 6515f37eae434c66d0eb9c5b48368bdcb44ea7a6 SHA-256: 104e9b55ec919cceb221f89ba33c8759004c33400e7589ff30a00b4ed7b42bd5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including ML classification and ClamAV, indicating malicious intent. The presence of numerous external URLs, many hosted on compromised or disposable domains, suggests a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically points to a link farm designed for SEO manipulation, likely to obscure malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://huntic.ru/uplcv?utm_term=vlive+update+apk PDF link annotation
    • http://daonshop.com/files/fckeditor/file/jegutefemojoxusixitudak.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/puzudipezukexulok.pdfIn PDF document text
    • http://logopeda-empatia.pl/content/file/bonemi.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/4327628253.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/userfiles/file/xubumufokorewod.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/lepagifebenaradudopegadu.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/19126896063.pdfIn PDF document text
    • https://telechips.com/ckfinder/userfiles/files/pitazu.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/31389507331.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/15042539882.pdfIn PDF document text
    • http://www.jysunshine-hotel.com/up_files/file/wusebafibi.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/91716899638.pdfIn PDF document text
    • http://cyuanmei.com/userfiles/file/diwelazagedifefudemukub.pdfIn PDF document text
    • http://another-partner.morefriendship.com/upload/files/70473703520.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/nonavelusimokitegegome.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/f02bb21487adaf7fd12eac3556a7d3fe/47465487177.pdfIn PDF document text
    • http://lonerangerfanclub.com/ckfinder/userfiles/files/10475191137.pdfIn PDF document text
    • http://grabnerestriche.at/33097358044.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16138d2a830650---riliv.pdfIn PDF document text
    • http://freestyler.cz/img/file/53993051354.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/39197812284.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354f9844150---wubapiwerokol.pdfIn PDF document text
    • https://nirmalujjwal.com/public/ckfinder/userfiles/files/58930767087.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_off0000ef01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF01 10120 bytes
SHA-256: e5dce4253ab1e6b8842fa7cd083ecb01aa6a31eb072387356e6bee89b161fffa
font_01_sfnt_off000105b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCB 19496 bytes
SHA-256: 724ce3a47d6ce7aa58669afb3892f9e89561ed6a12fdfc73ea3e28a5d141d43d