Malicious PDF — malware analysis report

Static analysis result for SHA-256 53a18131585b21e0…

MALICIOUS

PDF

84.2 KB Created: 2021-08-26 07:05:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0729f38d51e9c0848b32fc6bba87187a SHA-1: 3ebe2f78d2011ac5b8d0532509f119c98898e319 SHA-256: 53a18131585b21e0e29f0aeef208911879c7aefe84ae48d42f02c6556f859bc5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised CMS uploads, suggesting it functions as a link farm to distribute further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fdf140ca8fe---66723309365.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/6d4ehtqmip9skvl0oigqe4bghr/sutaropovarixivulaxowupaf.pdf
    • https://burgas-remonti.com/userfiles/file/zikirosowuguxupomew.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16092a10e8fe77---luxaviparugubuku.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/941fdd774ccaca4f67ffc96a7bfaaa53/pegilotixuxujegikojaja.pdf
    • https://carrieres-pierre.com/userfiles/file/62567483648.pdf
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/8m1hu6ee3koj8d425cnnqlat8e/wilomuririv.pdf
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/a415e9f3224fcc728260ee67d82db643/28535176869.pdf
    • https://www.swissfillon.com/wp-content/plugins/super-forms/uploads/php/files/6ac52baae5ea84c40a06c13d614cf1ee/rifikunovosolawabuvebezum.pdf
    • https://tekartltd.com/upload/files/59436653735.pdf
    • https://marupyara.com/fotos/userfiles/file/lufituwaluvoleparil.pdf
    • http://thegioidahoacuong.com/uploads/image/files/38427993326.pdf
    • https://digireg.cz/upload/35892291536.pdf
    • http://autofox.lt/ckfinder/userfiles/files/xovobutozi.pdf
    • http://www.odnpoznan.pl/fotki/file/file/68414036437.pdf
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/16021793014.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a73084de6---pozakonajeturikezedavoxox.pdf
    • http://kotolantopeni.cz/file/60894132539.pdf
    • http://latexindia.com/userfiles/file/vusibaxuzikujagoselazaj.pdf
    • http://colegiosantarosa.com/uploads/imagem/file/redesujogivugepofa.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1863cc1fa---parunitolinuzililovega.pdf
    • http://bhavalaya.org/ckfinder/userfiles/files/64983482029.pdf
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1611dce82ad010---33214435757.pdf
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/160cbec5a21092---nuforakutupujisima.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=bon+jovi+work+for+the+working+man
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db20.bin
108d1b04e1eddb1d3d87fe2412feae24cf2a38dc252e7fa23e34fefdd0fbb3a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB20 16576 bytes
font_01_sfnt_off000105f5.bin
afcc67f1cb938972619c8ce3bad92e584e55ddc2f012a859b34d19d7b10e8dc3
pdf-font-stream PDF embedded font (sfnt) at offset 0x105F5 2340 bytes
font_02_sfnt_off00011014.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11014 16792 bytes
font_03_sfnt_off0001282b.bin
d04823edc61204cf586e894c75827e5ee922c8c20e9cf4a3c3324c2492ee763f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1282B 10876 bytes