Malicious PDF — malware analysis report

Static analysis result for SHA-256 c61db57fca00c320…

MALICIOUS

PDF

97.6 KB Created: 2021-07-07 22:34:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: fabf8bfe6f7e73bfffb89b010d235d57 SHA-1: 3b88afaa662a138ddc7d1302593b102256b296dc SHA-256: c61db57fca00c3202bdc34bd33fc630b0e4e68f478e95e6accf101bbfa806dc9
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://wib24-admin.de/uploads/file/wunibilelejadegolazar.pdf In PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609414b1ee3e4---41419450785.pdfIn PDF document text
    • http://jocoseatee.com/userfiles/files/sowiroso.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/72161435608.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/noxarateliduraj.pdfIn PDF document text
    • https://dodatnojamstvo.com/userfiles/file/gawukivofokige.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/32948678565.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/d1b5635bc0da1a06cd66e0b3da497005/lipazetunonaxaz.pdfIn PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/694231525.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/15986923842.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/cda976fb468f3039d4405b2a36dabae6/25663001576.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/34543768171.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/jonefipekitoposusox.pdfIn PDF document text
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/21105021683.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1623518458.pdfIn PDF document text
    • http://aodaiminhhanh.com/app/webroot/uploads/files/wiwasiferaben.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160859349d5e2d---mizogibozifa.pdfIn PDF document text
    • http://apartmaji-zunicmile.com/uporabnik/file/givijasupuxokani.pdfIn PDF document text
    • http://brukbet.com/user_images/file/jeruwewiposulixejifebitof.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0fe8be806---63767536790.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/8johpcihjvlruvk6ha8g3p0i84/15409890887.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/87967590858.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b63aa0cd3f6---69014933488.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097cf5eb2b85---74993250211.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=how+good+is+salmon+for+youPDF 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_off00011b42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B42 17656 bytes
SHA-256: 1580553051c96514e73ee7d99ff76b051624311ad0dbc9605b2f38591e8124c6
font_01_sfnt_off000148d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148D2 10756 bytes
SHA-256: a03c1dd32c4370a2343e5d590a7401ed70c486c285e1b6d3040cd9308794ca32
font_02_sfnt_off00016149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16149 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1