Malicious PDF — malware analysis report

Static analysis result for SHA-256 79e16cb35875c598…

MALICIOUS

PDF

77.3 KB Created: 2021-09-15 04:32:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 00b0be969ce789d2a78fecbec9bddbe0 SHA-1: 774c2ccf787fbb980e7fdf8e230a8432784f8f97 SHA-256: 79e16cb35875c5980140573eeedc44a56d5f6ca7cc8835fef4b1bf0c00675c1e
164 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised websites and a heuristic firing indicates it is a link farm designed to host malicious files. The presence of a 'download button' lure further supports a phishing or malware distribution attempt. ClamAV detection and ML classification confirm the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://allytemp.ru/uplcv?utm_term=how+do+i+open+downloaded+files+on+android PDF link annotation
    • http://ahkjt.com/upfile/file/15444778276.pdfIn PDF document text
    • http://hypotekaprezamestnancov.sk/res/file/21579908810.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613703e526fe7---leziripakiro.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/15717498812.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141127f66779---99661879005.pdfIn PDF document text
    • http://rayanchem.com/d/files/bonatelavewimej.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/83043666964.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0193671f7---tetokuzotexosojexarub.pdfIn PDF document text
    • https://abicecream.ru/ckfinder/userfiles/files/dulefosojiwegikilubizod.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/e3d74c1127e4b07fbdd0a7ba920b2a80/xosesajofiragu.pdfIn PDF document text
    • https://aneri12.eu/res/file/wazixulowesapugusugeni.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/71905292511.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/96889243581.pdfIn PDF document text
    • http://qlinairnv.be/userfiles/file/beruxaburotavagage.pdfIn PDF document text
    • http://thestarbusan.com/FileData/ckfinder/files/20210902_56164F82B7FDCD3D.pdfIn PDF document text
    • http://flapboxes.com/userfiles/files/96563348659.pdfIn PDF document text
    • http://n3ss.ro/ckfinder/userfiles/files/68340067278.pdfIn PDF document text
    • http://rfinshaat.az/userfiles/file/zamekusaperopagezamo.pdfIn PDF document text
    • http://netdepphunu.vn/images/userfiles/file/89771636721.pdfIn PDF document text
    • http://zjbfjt.com/upload/files/mazelawapuwevozobu.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613805ab1849e---31323299066.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/gefafafeledijejavitujef.pdfIn PDF document text
    • http://officeharbor.com/pdtInfo/12936913792.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/51291869955.pdfIn PDF document text
    • 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_off0000cb19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e330.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE330 10468 bytes
SHA-256: 84a3fc6349ac11258a9538897aa607f7e6e42dbb6bfcc2a3eede413af5ff534a
font_02_sfnt_off0000fb0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB0A 17004 bytes
SHA-256: 92188079a3d0865249b05763093a412b3dcc58a93994a57f6d84a1b475ad2178