Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a0379429f4de2f8…

MALICIOUS

PDF

88.7 KB Created: 2021-08-19 18:42:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 72cded1f3351a92ee2767c6768f49368 SHA-1: d327ab4681281046b27448fa2afbc90cdc5fcc4f SHA-256: 9a0379429f4de2f8d94679dca0a2a013857d409af31b8527d9b96ed52084514c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing a large number of external links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded JavaScript stream, though not fully analyzed, further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 https://daiichitravel.com/uploads/news_file/vafigixuvikuveligibuko.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c6d31ebf2---33531753814.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7aa7de4120---pawenenadurujisilumofevu.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/73925e7f9b42340f4b129c67a8f73149/rilojifatejamava.pdf
    • http://mesterek.net/tmp/64830075040.pdf
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc7ec6d5f04---80182720873.pdf
    • https://thaiahpa.com/flash/files/wefokugimawijizaputixura.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16113df70baee0---midujilaxug.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b051368b8e9---84368868519.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/9c79e5ed611bed8a7be34f67696d8caa/91016591700.pdf
    • http://sadiqandsons.com/userfiles/files/jigosuluditomegoxarek.pdf
    • http://stcforanebanglore.smcim.com/www/js/ckfinder/userfiles/files/zoripanopel.pdf
    • http://banglenhospital.com/UserFiles/File/47710191079.pdf
    • https://bestwaynepaltrek.com/ckfinder/userfiles/files/rotojujapotadarafunivub.pdf
    • http://vksraja.in/fckeditor/upload/file/38199986762.pdf
    • http://shield-in.com/userfiles/files/54085826683.pdf
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/9ju70h9eqde7181o2d81i5ruse/zunusefowovogutekexob.pdf
    • https://n-zvuk.ru/upload/file/bimig.pdf
    • http://klenderbio.com/upload/files/viwosexaf.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c94771d345---busiziwiti.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/19sjkujgarseqm2kv721kfu49v/wekadefokofa.pdf
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/edfa729600ce30ae2a46fd2ae4e6ff70/83442491940.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9182e8a149---43828452368.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=speaking+activity+comparative+and+superlative+adjectives
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f487.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF487 16792 bytes
font_01_sfnt_off00010c99.bin
54f886d97b2cf85ef3570e571d0f932dbd08046a6cf284c376195488a2fad785
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C99 17232 bytes
font_02_sfnt_off00013948.bin
5b0883a09bd4ab6b610c2fd31413d668ce43b85e4d4394123703dafe4b33b928
pdf-font-stream PDF embedded font (sfnt) at offset 0x13948 11436 bytes