Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2f5e9f3f58fdc3f…

MALICIOUS

PDF

81.4 KB Created: 2021-09-02 15:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 85255767d808ddcbc7809c7637e62955 SHA-1: 4c994a9bf589b70c76eb7446b4a74e817b2d53fb SHA-256: b2f5e9f3f58fdc3f6fafc2b42a35eb6500bb55f1300af9af6858b9f0e8e6c70d
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the links and the PDF structure point towards exploitation of the user's browser or a vulnerability to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://queure.ru/uplcv?utm_term=formal+language+and+automata+theory+tutorial+pdf PDF link annotation
    • http://mmprogetti.it/userfiles/files/sulewimufiwusado.pdfIn PDF document text
    • http://vogiantinhmach.com/media/ftp/file/13704329957.pdfIn PDF document text
    • http://avision-italia.com/userfiles/files/saguxisukodananufote.pdfIn PDF document text
    • http://shesob.com/file/files/46659428994.pdfIn PDF document text
    • http://altinay-law.com/images/file/dunezifinawododuxug.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/28481904667.pdfIn PDF document text
    • http://abwingsde.com/uploads/files/mefexujarozufijit.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/rejoduwatowenunisu.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/69678183099.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/gdo4ilk681c38682oulcr5s81n/54030723150.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/26c0d06b2da2a9f2755abcb2b89bd025/60274523650.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/29776568159.pdfIn PDF document text
    • http://emke.hu/uploads/ckfinder/userfiles/files/senexawego.pdfIn PDF document text
    • http://medtravel.pro/images/hand_uploaded/files/fufasizevutokenut.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/wewajupobiwixu.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/jifibugalinilofi.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160ae001c895d7---zogosalibodasa.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ec42ba2e245---88310513293.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609be4232ebea---gafafisewoxoneliwuzole.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/86rkp91q6199v1d9horvhkqdpe/88498035491.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161282e69c339d---31130226038.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9082764124.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_off0000d5ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EF 10968 bytes
SHA-256: bc9ba756a9e0f05bded4337e72c040f77769005824e16552a6a238ae1b19b1db
font_01_sfnt_off0000eef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010707.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10707 18596 bytes
SHA-256: bbb4364b408b9746131a2285b754d5f067033f68f6baca5b1bc51428994f4108