Malicious PDF — malware analysis report

Static analysis result for SHA-256 97166c815b162136…

MALICIOUS

PDF

73.0 KB Created: 2021-09-12 19:50:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 992ece375219cd16c4bc2cb918aee8d6 SHA-1: 8a6140266f308a155547813f97979ee00f57a29d SHA-256: 97166c815b1621361e8a305b89805a6b366c702591ddb13f67f3dbcc9acda2c6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised or disposable domains, forming a link farm. The presence of embedded JavaScript and a high ML classifier score, along with ClamAV detection, strongly suggests malicious intent, likely for phishing or malware delivery. The embedded JavaScript is a common technique for obfuscating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • 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://to-kajihan.net/js/upload/files/42413941612.pdf In PDF document text
    • http://protok.pro/upload/files/zasokavesi.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/20542810525.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/sofokamenoxulegaxefunub.pdfIn PDF document text
    • http://gpmpoolandspa.com/ckfinder/userfiles/files/mebafuguwemafuparafaroj.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/59140780836.pdfIn PDF document text
    • http://biosurfest.com/userfiles/files/27035734304.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/pemenokis.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/83698224404.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/dozopoziritigig.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16131f95c15856---89351847936.pdfIn PDF document text
    • http://tatishev.ru/admin/ckfinder/userfiles/files/7169367260.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/680c55611c9f01f4d806de93b23f2f03/tobagewugafonovek.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/47929298374.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/gibolebegalipirisav.pdfIn PDF document text
    • https://preciseenergygroup.com/media/36667440426.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/24726396037.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/ac8be5d0eabe6dc465f88f371a6bc90c/jexikalekaxesip.pdfIn PDF document text
    • http://cesurmakina.com/userfiles/file/mosivatapozebenaroduvo.pdfIn PDF document text
    • http://costruzionibulagna.it/userfiles/files/tejowabovotuseditejebu.pdfIn PDF document text
    • https://olboihorgaszto.hu/editor_up2/39219137005.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f185ab36be---19033985933.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/nanusesukotigatebinigub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=wordly+wise+3000+book+8+lesson+8+answer+keyPDF 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_off0000bc13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC13 11068 bytes
SHA-256: aeec94cb196055862930cf115b76bc2b662719bc4c4cc59857c6bc22d5989502
font_01_sfnt_off0000d60c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD60C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1E 15780 bytes
SHA-256: d905b6080300386200b3e1b6716c8b86729abdb725a357bd5b0285d13f2a84bb