Malicious PDF — malware analysis report

Static analysis result for SHA-256 51d68fca435f0941…

MALICIOUS

PDF

80.4 KB Created: 2021-07-05 00:28:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 35d6e4342e3d383590e72300583c75ba SHA-1: 0965587720f70175cf4f515150cf500f8831f31e SHA-256: 51d68fca435f094125ba209b248ae1683eb97fcacd11c67d33613b8052bd7bc4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is a PDF that contains numerous links to external websites, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, suggesting it is not intended for human consumption but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://drafthe.ru/uplcv?utm_term=french+2+textbook+pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d43b3368d5---rojalamubapijogukitanu.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/40e66c21764960065f789c5b4661eb61/sizujopimadodezukodu.pdf
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/sekorukiki.pdf
    • http://enricobarraco.com/files/33330413637.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743e9b2ada3---5024072176.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/9547346524b36a5c5024b7a3415dc84c/2461859063.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608785bf95e06---xumoxuzumo.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/49iu93du975qu60ffiqlgmo97t/18882311562.pdf
    • http://mauchlineware.com/html/chapelstreet/web/userfiles/files/30777667517.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608391f3cb220---49689174128.pdf
    • http://a-swiss.com/upload/userfiles/file/79505308678.pdf
    • http://classicalgardenornaments.com/uplds/file/jorewemivukoj.pdf
    • http://pumarecovery.com/userfiles/files/84446413562.pdf
    • http://wsp.pl/userfiles/file/46886602374.pdf
    • https://noddy.nu/images/file/bozokizudekilojejipeduwem.pdf
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/07e6a1fec37112bd5abb1bcbe396fede/jevojavixomepebupafudase.pdf
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/nebafurijikidil.pdf
    • https://viboot.com/ckfinder/userfiles/files/megugeniwivulidomi.pdf
    • https://afra24.com/basefile/afra24/files/25181065674.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd932a636f---4198286253.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609767082c1f9---56045576971.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093a7071b5c8---fuxitenenop.pdf
    • https://conexusinternational.com/ckfinder/userfiles/file/16960737436.pdf
    • https://jurad.eu/files/file/kowoxiwedep.pdf
    • 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_off0000d841.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD841 16792 bytes
font_01_sfnt_off0000f058.bin
aa4f98ccbdd467ed91dea6c16b9bf9571024b06442a7b2137e30f739584e036f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF058 10680 bytes
font_02_sfnt_off00010889.bin
447bf5ffcf3bd755d29f8f2066ba459ec41f9752450a399c79dc7ca2a4831e32
pdf-font-stream PDF embedded font (sfnt) at offset 0x10889 17232 bytes