Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d770b883d8b961d…

MALICIOUS

PDF

68.1 KB Created: 2021-09-13 06:45:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f97f2ae26b17e4e0fcd2d744596f9a9a SHA-1: 02fd61817bf80f5195beb33201e580e8c350626a SHA-256: 8d770b883d8b961d6b119f5832ae025c1572d66bbad8366049b6ebfa70c5e5f9
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it likely contains malicious content. The heuristics reveal it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. The presence of numerous URLs, some pointing to known compromised CMS upload directories, suggests a phishing or SEO manipulation scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://archism.ru/uplcv?utm_term=lagged+io+games PDF link annotation
    • http://ourdesign.hk/ckfinder/userfiles/files/tomujilowowasejilotiz.pdfIn PDF document text
    • https://plasy.com/uploads/file/26047093611.pdfIn PDF document text
    • https://sharkovinkom.com/sharkovinkom.com/ckfinder/userfiles/files/zukolon.pdfIn PDF document text
    • http://pinxedien.net/upload/files/70336275806.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371ad60dc6b---kinamapilegijidesibus.pdfIn PDF document text
    • http://classtool.info/upload/files/17173217908.pdfIn PDF document text
    • http://ildongwire.com/userfiles/file/wokogup.pdfIn PDF document text
    • http://papienbanana.com/user_file/file/5538154739.pdfIn PDF document text
    • http://sevenseahotel.com/uploads/images/files/13270568598.pdfIn PDF document text
    • http://madurastones.com/userfiles/file/tubejopavewanevida.pdfIn PDF document text
    • http://komodovo.ru/upload_picture/fogugomepod.pdfIn PDF document text
    • https://patidarpalanpur.com/web/k/main_admin/ckfinder/userfiles/files/vomobusiki.pdfIn PDF document text
    • https://polandpools.com/contents/files/tiwoxugukerizuwiwepugow.pdfIn PDF document text
    • http://scantech3d.com/files/muluxuzefe.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/4df6som6ssjaedd59u1lv1p0jh/tuzenupawu.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613532efab904---17466447959.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/94908685148.pdfIn PDF document text
    • http://studiopol.com/userfiles/files/60718692670.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/momalapaziwuzal.pdfIn PDF document text
    • http://odumakus.com/uploads/files/retebidoxofupigezekoxu.pdfIn PDF document text
    • http://stnicholasway.com/userfiles/file/julitukiz.pdfIn PDF document text
    • https://palezieux.com/ckfinder/userfiles/files/jafedepupurirojukira.pdfIn PDF document text
    • https://venus-forever.com/image/files/86466156987.pdfIn PDF document text
    • http://fjsxsx558.com/upload/files/89834084031.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_off0000af5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c76f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC76F 14856 bytes
SHA-256: 623b8e3ce3d334650a9d6a96a9838927bf137dfb863b75b78134071f3a2d59d2
font_02_sfnt_off0000ed00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED00 10200 bytes
SHA-256: c55f86988a194aaba3303b763d9d7fd22fe4ae3809d969c0080f2cbdc77df3d1