Malicious PDF — malware analysis report

Static analysis result for SHA-256 10fc16827a7f6394…

MALICIOUS

PDF

72.0 KB Created: 2021-09-03 19:01:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2fe7281b42c753ce1d451eae48a5e580 SHA-1: 31875c37e69cd7be9f2928e2d6e7cb02f548dd44 SHA-256: 10fc16827a7f6394b383fb462a70180d0305200256ae264b8b9c2c416216e7c5
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 upload directories, suggesting a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites or download further malware. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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 http://dienlanhlongan.com/upload/files/6853841340.pdf In PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/9476528742.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/mazibigiv.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/wolukufatekesakivevu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161078f995ff96---59625766739.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bc642999c32---32983232939.pdfIn PDF document text
    • https://biovuspharma.net/userfiles/files/wubixitevuvulabogulewixaz.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/2fqaem1aql196eg45bs6egor57/12895646659.pdfIn PDF document text
    • http://rhodeislandalpha.com/clients/56223/File/nedubozelagotaromipekij.pdfIn PDF document text
    • https://ms01bet.com/contents//files/pusavedugudukedizud.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/baloriwipe.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161310e5e438d3---44433293401.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/70af008ff2fbb0b8d796afff623315a0/10881773510.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc8c91a675---27061430329.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/0e1906b88cd16a389860f1a556ea96da/repekageto.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160c0e48f410da---pelenazajobas.pdfIn PDF document text
    • https://santevita-bg.com/ckfinder/userfiles/files/banaw.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/70046535671.pdfIn PDF document text
    • https://www.bakirkoytemsilcisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075cfe80789a---motaz.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/wiledexakevo.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ff9ce0401---guvaxatogedofatuviso.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/miravokigopuvebujisifob.pdfIn PDF document text
    • https://apronorte.org.br/ckfinder/userfiles/files/37262281305.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/fd967c0456681c8d37db58ae97cc44e7/3172648184.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/a648770149eaf817c9832d4baff1f333/gupaj.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5eaa0bd82---todigezada.pdfIn PDF document text
    • https://doublehair.center/upload/ckfinder/files/vixefefemow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=less+than+greater+than+worksheetPDF 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_off0000be33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d64a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD64A 10384 bytes
SHA-256: b8609dce55616a3be66e14f7de65fed1e37f33725663cdc2b152aa78f79497ec
font_02_sfnt_off0000edd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD8 14392 bytes
SHA-256: 84a63b93345966113c7dfc53850fc3e6e1ab5c39497e539e9d3a44a775abf7bc