Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e3c90fb8e13ceb…

MALICIOUS

PDF

93.8 KB Created: 2021-08-08 19:41:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 16dacd9a90686555496c34253a7a2906 SHA-1: fc2615c72c4840775e2ec1735ef839792dc024e7 SHA-256: 51e3c90fb8e13ceb7c239d24280c050e0e10c0b9b9b493f088f6585a7fb59c65
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16093f623b82c2---87890672506.pdf In PDF document text
    • https://autotronics.vn/userfiles/file/37593811195.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf7b4e51e4---gajunugojipatuzi.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16075e7d292f17---nepiviruruxeris.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/cecf7003ba8877398cdc05efc305669d/92633494434.pdfIn PDF document text
    • http://mxagproducts.com/upload/browse/file/44943693233.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/megifisikitu.pdfIn PDF document text
    • https://safrano.pl/userfiles/file/40430874583.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/96954773103.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/uh5grtm39tbcvg28tu0ud9fgn0/1726630705.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/vanuwesuwefigij.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/3t5drabpns9vpndpcfmukvmah1/figewuxudotaze.pdfIn PDF document text
    • https://valleyrestoration.net/home/apf/public_html/ckfinder/userfiles/files/lodexalevifunopalu.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a62c1d29d68---vaduwonigolexejomi.pdfIn PDF document text
    • https://rmp-familienanzeigen.de/cms/files/negezifof.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/7c197b0b7ec20c557b75bcc720c13c87/fowurasijolurifa.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160aabc87a0a62---fetigawem.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608860186abd3---58101047889.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/32154853329.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/ab900792d4f8b4c6adb1745c10352f20/48871325074.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/gejesivavifigire.pdfIn PDF document text
    • https://vibanghanoi.com/uploads/files/xiremuxogewagilav.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086888829f40---rirotikibof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+increase+height+after+18+in+1+month+for+femalePDF 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_off00010aa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA2 11120 bytes
SHA-256: 4f4cc2eaee1b1abe28e81eec474d2845539420b0a154484b22e64d6d9c2e5f27
font_01_sfnt_off0001247a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1247A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013c8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C8C 16900 bytes
SHA-256: 729011bfe697794e150b9e11a9170e5a87fd87993ddf17b33b8eb15f1cf991be