Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5906a7d7dab88b9…

MALICIOUS

PDF

85.6 KB Created: 2021-09-10 20:02:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bf3120bb67e93d8e40788325af530243 SHA-1: 4467c08441e6127af47266ba769609f669210721 SHA-256: b5906a7d7dab88b95937068787779dc2cce08075553baf4fffe2780701ae55da
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to PDF files on various domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links are characteristic of a malicious document, potentially leveraging JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://webkapper.nl/ckfinder/userfiles/files/fupaxomodunukomavobok.pdf In PDF document text
    • http://villalapinetafavignana.it/userfiles/files/jizosa.pdfIn PDF document text
    • http://www.serge-valentin.net/ckfinder/userfiles/files/rekope.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/89957937391.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/jujogetaz.pdfIn PDF document text
    • https://makojudo.pl/zdjecia/fck/file/zegigani.pdfIn PDF document text
    • http://mgtofubbq.com/uploads/files/zixofaruvusatirem.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16132aec2b0ccb---sopidutefezarulujedawulil.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/31862448705.pdfIn PDF document text
    • http://yjccnc.com/upload/files/85490082287.pdfIn PDF document text
    • https://ijieet.org/ckfinder/userfiles/files/9566972919.pdfIn PDF document text
    • http://dr-temt.ru/images/file/zusenomewavufan.pdfIn PDF document text
    • http://kapsalonindex.nl/images/uploads/28161972311.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b8e3344f64---tepenikoberowisok.pdfIn PDF document text
    • http://j1ent.com/userfiles/file/20210910212117.pdfIn PDF document text
    • http://honderhotel.com/UploadFiles/FCKeditor/20210909095056.pdfIn PDF document text
    • http://business-plan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/tapisiteguzepupus.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210905_D5062D8635D79E09.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/dinopisiwuduxudunuk.pdfIn PDF document text
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/88940604195.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/logujuvixawigesujuwiwetiv.pdfIn PDF document text
    • http://laihoawedding.com/app/webroot/upload/files/38345883858.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/18566801007.pdfIn PDF document text
    • http://tyros-club.de/userfiles/file/jizeduwujulujesazokanovof.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/sutiselod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=screen+mirroring+android+to+pc+appPDF 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_off0000eaf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAF1 10716 bytes
SHA-256: 03a607a8f14b226dc096eb0a003d9e9aec1a13dd996127cf5cdfd952bd7de729
font_01_sfnt_off0001034c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034C 17400 bytes
SHA-256: c367dd55f3f1f0791dc42a5153e88887d133c62cc025293f34ba98ec8fa3ab4c
font_02_sfnt_off0001308b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1308B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1