Malicious PDF — malware analysis report

Static analysis result for SHA-256 5287539e23b600fb…

MALICIOUS

PDF

72.3 KB Created: 2021-09-26 12:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 36f179d9dbdb65041f0b0408b1459734 SHA-1: 363bfd79d462383183fb9d030f8dc810fc2beda6 SHA-256: 5287539e23b600fbe0293fdf9c100de50d84f78272fba1e1782a48bbabffebb7
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also exhibits characteristics of a link farm, with a high number of external URIs pointing to various domains, likely intended to redirect users to malicious content or phishing sites. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://harnettcountyhba.com/userfiles/file/giwoduvozamoxigawaxo.pdf In PDF document text
    • http://askaudit.ru/price/47938975411.pdfIn PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/tetezij.pdfIn PDF document text
    • https://olterus.info/contents/files/70967970188.pdfIn PDF document text
    • https://shibbirs.com/media/files/43007640964.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/161347c754c169---vagomuj.pdfIn PDF document text
    • https://mgs-on-track.com/uploads/misc/files/talodumalekuforik.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145f0a55e925---rugezesuzi.pdfIn PDF document text
    • https://ht-cooling-j3t.com/contents/files/29101937809.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/11730971558.pdfIn PDF document text
    • https://hyosung-gulf.com/uploads/file/98916558242.pdfIn PDF document text
    • https://diamond-marketing.cz/soubory/valobowaza.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/totoxipaxoxopovomaxejule.pdfIn PDF document text
    • http://jamones-luna.shopcloud.es/ckfinder/userfiles/files/47599212334.pdfIn PDF document text
    • https://j26clean.com/upload/files/66917685118.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/jozipujofiferofabugimimi.pdfIn PDF document text
    • https://branches.armz.ru/media/File/rajefi.pdfIn PDF document text
    • http://depcip.com/app/views/panel/ckfinder/userfiles/files/pazifafuguwejobibikito.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nebutapotavezujixidovobiv.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/60085235604.pdfIn PDF document text
    • http://uran-berlin.com/userfiles/file/11371933566.pdfIn PDF document text
    • http://z500.si/files/8496999250.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/welenogazakizoboz.pdfIn PDF document text
    • https://clic-essc.ch/ck/ckfinder/userfiles/files/55444913133.pdfIn PDF document text
    • http://hoadondientu-ptp.vn/images/ckeditor/files/ravatezapoxaze.pdfIn PDF document text
    • https://www.agro-zavod.ru/app/webroot/js/ckfinder/userfiles/files/76967351930.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=apk+to+ios+app+converter+online+freePDF 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_off0000b61b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB61B 10612 bytes
SHA-256: dfcbf2ea6a393ef38d3c9fa4857611b3d58f9bc247226093675d564ad474fc6f
font_01_sfnt_off0000ce99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AB 16876 bytes
SHA-256: f38f892e0fa0d59e26555cc9fd0ecfda5daec534311013103324f942b9df9024