Malicious PDF — malware analysis report

Static analysis result for SHA-256 243d527c6eb663af…

MALICIOUS

PDF

87.2 KB Created: 2021-07-03 11:29:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: ff081bd0bb82ab4a64cc4b1c7796dd2b SHA-1: 95a97a2b9ce0d358a4b85ba471b1992ae55fa0c9 SHA-256: 243d527c6eb663af9019fb1342270f2f77e4c38aca6603a73e3117bb83429fbd
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs further support the attack pattern of leveraging link farms for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/7a528104a30a21f69994acd49c53f9e2/bemesesimunojudiko.pdf In PDF document text
    • https://hasekei.jp/userfiles/file/87501881359.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/d27aeef8c590af24b156f0d6efbeb89e/79499821667.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608084946ab7b---bilupexozox.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/4f5975c53aff87753578fef7a40339f5/32594555204.pdfIn PDF document text
    • http://bidwoodmachine.com/d/files/folusuvelabituz.pdfIn PDF document text
    • http://airlineclassof66reunion.com/clients/c/cb/cb51827d251551eca15067b3b23580a4/File/jovuwasujinupi.pdfIn PDF document text
    • http://canoeing.by/pics/files/gobetekusekoxiluzibidedef.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/ee905e4f2fd8c84f37e4d429ca6e1865/40745728858.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/daff3fe7b121e5c1712e70c368b2865c/70708267358.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/kesasarebes.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d77e98fc82---86462980035.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/5d18a0656c3ad9a6c0f9cdc9f6905200/66246847322.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607bce6da04cf---rurumivufokilub.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/0a6e201820640d3fdc38ec902b484586/40121463562.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609b65aa4aa61---49955519364.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/g32qg9ihf82s6jv607mfgd66d4/85666952768.pdfIn PDF document text
    • http://skoleniridicu-online.eu/ckfinder/userfiles/files/71504849047.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d95f8705c4e---55204768834.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/c9f0b147ad71dfb246516da17bfb6077/davegezerumiwi.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/wepudawujigiwelogabix.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/904ec5df941ec75836385b8601fdad84/roridesivalopo.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/97636190792.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a113c8b2344---jupexerizu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=diff+between+kcal+and+calPDF 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_off0000f169.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF169 17928 bytes
SHA-256: 525035b8563cd8e8f63f59576355441eb7a759b2ad2de9b63c0a77eb1fd36124
font_01_sfnt_off000120b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120B0 10400 bytes
SHA-256: 101c3ae5efebaff78d2d8dfc33d1310eb939832b0f33c5e894ed1714c0cdae5f
font_02_sfnt_off0001386e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1386E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1