Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b4b6f9996deabde…

MALICIOUS

PDF

97.6 KB Created: 2021-07-22 11:09:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9e693a4d55b57abff96d03ad8ec8046c SHA-1: ad78cf3375097129b4460a901e3fe10a470e9f76 SHA-256: 6b4b6f9996deabded995a6213de8d983b7bb79037f52c86a35d98dfde75fd91d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple compromised CMS upload links and SEO-related URL parameters further supports the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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://forumhrdbekasi.com/webroot/userfiles/files/gezurewo.pdf In PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbfdc5d902---99993119196.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/04be6f7cf6f493aab3ea1aa4bf5c4d33/7047596126.pdfIn PDF document text
    • http://taniaandjohn.com/clients/874109/File/wazazasufezaropo.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/0043c747cf00ed1606e40d2627b5ae53/nonubamidikodamo.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a74ff3cafb5---relidegumag.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/piwamewixiji.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a19910c570f---vamasir.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609838d1e0f25---28298072283.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/uchlumd61q9eddki26ah1s9bqn/65104794143.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e0e3ab0898---33309776133.pdfIn PDF document text
    • http://fly.no1-yes.com/userfiles/file/19576474031.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c4c37a97e---kegidane.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/64fb8575ea1dfaa039dcf5774e58efed/wekuradubit.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/1608c06d2c83e2---puledunufuvageva.pdfIn PDF document text
    • https://mmszke.hu/files/file/powexuwijamiju.pdfIn PDF document text
    • https://myvideoclasses.com/ci/userfiles/files/dotinadawex.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/u4ddbt9rghe9i1hcchd8qmo98o/90886491053.pdfIn PDF document text
    • http://ilovechardonnayhills.com/userimages/liwixafepi.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e3e9c17c4---jepok.pdfIn PDF document text
    • http://bielwod.com/userfiles/file/96137231432.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/zaxinamo.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d1de8ec7d7e---tifefewokofetagafe.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/64754335215.pdfIn PDF document text
    • http://jevades.com/aircraft/fckimages/file/povepiw.pdfIn PDF document text
    • http://eshop-kocicinadeje.cz/files/file/44606693789.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=best+sketching+pencil+for+procreatePDF 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_off000119c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000131d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131D7 17504 bytes
SHA-256: 9ad0c9aeeb3640694cc73a116bda46c912345ace111293834ab38108a9684f24
font_02_sfnt_off00015f64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F64 10904 bytes
SHA-256: fc7c254f42b74a84d6ada57bd528afeba7405636828eebda70e73260e80c9038