Malicious PDF — malware analysis report

Static analysis result for SHA-256 849b0b83539a91b0…

MALICIOUS

PDF

68.3 KB Created: 2021-09-28 10:26:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 99193db698c43161cd222f8728d9061d SHA-1: 84e20c80f4e0770b26794f39d2bd84b864375bdb SHA-256: 849b0b83539a91b0c13c3bc6a2f0e46ccf0f118aa78cc90122858c3260e7317d
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to various websites, including those hosted on compromised CMS platforms. The presence of numerous links and the nature of some hosting suggest an attempt to lure users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 http://hkbroadwin.com/userfiles/wenurugexopule.pdf In PDF document text
    • https://eghamatsafar.ir/basefile/eghamatsafar/files/xoxukilofojologavuxofar.pdfIn PDF document text
    • https://thieumaunao.vn/workspace/develop/uploads/ck_upload/files/2929648168.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613013e2cdabc---15869670421.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/lidukebudibol.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/sufenuxileduxo.pdfIn PDF document text
    • http://leoclubmarsala.it/userfiles/files/32450092379.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/1756235984.pdfIn PDF document text
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/82904312568.pdfIn PDF document text
    • https://thebottombillion.com/business_school/uploads/file/tevagopoxirufovotut.pdfIn PDF document text
    • https://subarini.ro/mm/file/zodozizu.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109090945457647.pdfIn PDF document text
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/fozunu.pdfIn PDF document text
    • http://186086.com/upload/files/levudufivika.pdfIn PDF document text
    • https://artistprasanna.com/userfiles/file/nolupasoruj.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1613a019a5ccad---96786917216.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/1310232084614305009dcf4.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/bodezepematu.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/jaxuzadurejerisafitata.pdfIn PDF document text
    • http://theartofdesign.nl/ckfinder/userfiles/files/ruzaditebolebuvabofoparu.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/e54b4463d3fb37e98bea62273bbd448f/muxisotejeguritakerimi.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/94309128625.pdfIn PDF document text
    • http://riccaassociati.eu/userfiles/files/72369875564.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=wifi+hack+for+android+9PDF 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_off0000aec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEC8 14928 bytes
SHA-256: 46d1aa09828a9a4d8736f8bf4f41cdf1bb975b9e5995a94ed912d2c98f5b26f5
font_01_sfnt_off0000d452.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD452 10384 bytes
SHA-256: adb3d8b22d3c69b967bef20ce7e1a55935812b10da4c309d8d79b24feb5c169e
font_02_sfnt_off0000ebc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1