Malicious PDF — malware analysis report

Static analysis result for SHA-256 1df26abc519e9b87…

MALICIOUS

PDF

72.8 KB Created: 2021-08-31 09:49:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0321dc7c3b1f9c0cb6f6d297ae126d93 SHA-1: 549e6664b8e25a7b0466e025b166dc9c8d71fba4 SHA-256: 1df26abc519e9b87f2471b4d3815884eeb85e296d37521bf41f7d6d0dce843e9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

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://archism.ru/uplcv?utm_term=17+month+old+not+sleeping
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/43fc4db61d494f9e39c21542c25821f0/pujenulotilusewasoti.pdf
    • https://fsreloading.com/userfiles/files/mobavuwifigige.pdf
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/16091af72b5a4a---92209755893.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/9v9qgafjf12j7jvsmmh47pq8jb/runerusowo.pdf
    • http://gayaarchi.com/userfiles/file/20210629220328.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/591a27bc458d371731801f18e85fba15/dusutafov.pdf
    • https://panama4d.com/contents//files/sajatir.pdf
    • https://sasalidayanisma.org/uploads/file/74335595714.pdf
    • https://dcimx.com/files/lanejalebe.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160900fcddf409---lazuruwetivif.pdf
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/jibozofaf.pdf
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7498cee59---gijoj.pdf
    • http://www.reenactmentmarket.eu/images/wyswig_images/file/94882403581.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d90b7c307bf---dapewipodi.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160760cf707dbb---mofularivosi.pdf
    • http://zigzagontwerp.nl/sites/default/files/file/91557593226.pdf
    • http://goldmustang.ru/files/files/mikefufanowexovaxor.pdf
    • http://bjhtdszdh.com/v15/Upload/file/20215162127424582.pdf
    • http://irvinenott.co.uk/ckfinder/userfiles/files/11170555566.pdf
    • https://karapinler.com/calisma2/files/uploads/nutitarotokid.pdf
    • https://pensiuneavalentina.ro/app/webroot/file/moxozibobudokevinomovig.pdf
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/jogaje.pdf
    • http://cityclick.it/userfiles/files/73284783935.pdf
    • http://machinegroup.ru/img/outer/files/17478203008.pdf
    • https://vgi-vn.vn/app/webroot/img/files/demajilepimusitoje.pdf
    • https://noihoithanhtuan.com/media/ftp/file/720443542.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_off0000bdde.bin
34a6490dea3d70e89c11c8a6d8bd562b32307865a3f9b62c367f2fb4deeaab2a
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDDE 15704 bytes
font_01_sfnt_off0000e5da.bin
439f3dd097670a8c2d740cce2aba34db0bcbe24db59aa7f920ed75e88f63485a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5DA 10584 bytes
font_02_sfnt_off0000fd9a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD9A 16792 bytes