Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6a9462c9b21fd10…

MALICIOUS

PDF

88.4 KB Created: 2021-09-18 10:41:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3d1129b90aae80bc9be7ee56883a07c9 SHA-1: 28cdb26c03a6f89bb925d7e7766f6cecaceaefd4 SHA-256: c6a9462c9b21fd10ff64e372f767a947922a70a98d7c28fe6688a78b2c26c4ab
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution scheme. The primary goal appears to be directing users to external sites, as evidenced by the PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://infrive.ru/uplcv?utm_term=vidmate+fast+downloader+app PDF link annotation
    • http://all-vehicle.net/js/upload/files/notamen.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/49800811864.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/puxokufapitifaxujidemu.pdfIn PDF document text
    • http://hichipper.com/hichipper/uploadfile/file/2021091403284873499.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ede528f5a5---85863898620.pdfIn PDF document text
    • https://peoplehelppeople.net/uploads/File/51744332624.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/kunerode.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16140e158ec5e7---mogukapu.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/33815120859.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/nitavuli.pdfIn PDF document text
    • https://srldirect.com/ckfinder/userfiles/files/jusefojavan.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/xaxus.pdfIn PDF document text
    • https://wemservice.com/ckfinder/userfiles/files/nagejalujojomulevuwududo.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109091534053228.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/afae0971a71f6cec8eb2d4aff942b89b/kipubuviremebopesuzajes.pdfIn PDF document text
    • https://rajaunited.com/contents/files/wujexeso.pdfIn PDF document text
    • https://rosycaffe.com/file/10151036471.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/kapis.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/puxuvebejigozorupugejapil.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/wopesutugafez.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/20ddba345ba759e6df0bc5b09da99d6d/xejatotuzofuw.pdfIn PDF document text
    • 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_off0000f6b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B3 10712 bytes
SHA-256: 32f5820fefaf9630edb6c0216bc644ae8fa4279495e7ca13b22ca8748a597013
font_01_sfnt_off00010f4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F4E 17192 bytes
SHA-256: 2ccc52ca51c8b7c35a7017651289d244a0f08883650eda050d829cf5e6abe100
font_02_sfnt_off00013c15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1