Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5131435e69859f9…

MALICIOUS

PDF

87.6 KB Created: 2021-07-01 15:59:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: c2139668955b01dd735827bb6ba48eb5 SHA-1: 15ddeee06182a7cf2fb5470a0c8dc6fe2f199307 SHA-256: c5131435e69859f98700adbe48c3ecc9626f11ad213aa89407dbbf318f250ca8
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan distribution attempt. The heuristics reveal it functions as a link farm, directing users to compromised CMS uploads and disposable hosting sites, likely to download further malicious content. The presence of a 'download button' lure reinforces the deceptive nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://archi1919.com/smlclub-files/file/tusoxo.pdf In PDF document text
    • http://hotelgiottotorino.com/userfiles/files/10361120591.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/90136149295.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad8c057f193---bivifezixuvatadumubalil.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16090e9865efbf---rujuwitilugudafozatin.pdfIn PDF document text
    • http://cy2hand.com/userfiles/tosatazuvulip.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/dovudorunilobobulabi.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/f3f88e03cdab79470063f988c453538c/jogekinagara.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087f290dfdab---bidarifiwabum.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/998980e87ec270110e73a9735747236c/62727966604.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/xujenufesedoxug.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/89769607007.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfcf29629c0---tizivisaseviganenilodubus.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/26e3e41ddc5f9223daa6efdb6b92b648/kukodepefururefisasoxav.pdfIn PDF document text
    • https://www.treehousecare.org/wp-content/plugins/formcraft/file-upload/server/content/files/160789f50cac43---50575741108.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/ad76c11bea3645ce014586f0e29f1c8c/jalimu.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c163d96a2---detibefogawuzum.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/zisevuvisebokemetuko.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/5404d48ba35ecc0faaaadbb16d871b1c/21096645493.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/6409b74352bf96f98a241dc77da98dd1/kekaxatogob.pdfIn PDF document text
    • http://yejida.com/userfiles/file/zigejaporaxexatirobuzogup.pdfIn PDF document text
    • http://bdn10.cz/files/file/14082463593.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/fv4c38rmtn4aic2ii3skt6d92c/44874589177.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073421a53107---24331539000.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=how+to+enter+data+in+pdf+documentPDF 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_off0000f3d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010be8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE8 17044 bytes
SHA-256: 81a5d851cce0f7da72a607c4c9d1807372aa3ee69a5fa46ff68a75af9e0e56c9
font_02_sfnt_off0001385c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1385C 10744 bytes
SHA-256: 4810ac2a3eccc03b7d9870adfb565af80897f45c6b8344b28aad231e1eaa50b3