Malicious PDF — malware analysis report

Static analysis result for SHA-256 f99d0a216e82e570…

MALICIOUS

PDF

73.8 KB Created: 2021-10-12 14:47:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 15af4a55d55a561dca8e554e238990a2 SHA-1: 9a83cacfcdcfa813deb8c7463a817857aa0ad68a SHA-256: f99d0a216e82e57061e37cf3c2f74c4353bf8f90b4a83a9f54651a32bdac6b02
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including ClamAV detection and an ML classifier. It contains numerous external URIs and link farms pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://huntic.ru/uplcv?utm_term=skewness+in+normal+distribution PDF link annotation
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/59f1f9b110a4fb6dc48534ae5c5f59f5/43310858660.pdfIn PDF document text
    • http://abbaorphancare.org/survey/userfiles/files/41577847531.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/72960218946.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/sarabagipa.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/23443460527.pdfIn PDF document text
    • http://rem-stroymont.ru/img/file/gagojizuxowojefodufukub.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/mamekaji.pdfIn PDF document text
    • http://wiskind.com/filespath/files/20211002161836.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615caeb188055.pdfIn PDF document text
    • http://globalbizkorea.com/userData/board/file/94534721406.pdfIn PDF document text
    • http://0953057778.kad.tw/kads/ckfinder/userfiles/files/xuwakujoxumovin.pdfIn PDF document text
    • http://sport-zavora.cz/data/file/niwewotare.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/64307729983.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/63943f3672eddba6f3402f1bbf0ab8fb/fekolilubikexumogotutof.pdfIn PDF document text
    • http://epplast.com/files/file/80682061212.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/f10c20cd9fa3630c5c0051b805bc01ab/jabeta.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/nasitununode.pdfIn PDF document text
    • http://www.tahi.hu/ckfinder/userfiles/files/nubididujux.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d031f74c2e---dorisinabanulevuxutamijik.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/7531749322.pdfIn PDF document text
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/18329908000.pdfIn PDF document text
    • http://hotelbelleepoque.bg/userfiles/file/pijifodagiputew.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_off0000bdbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDBB 10904 bytes
SHA-256: c6c8ff0216c3a99a11acbacbb4df131bff099bfffc6c727f5e47358c84ef7a66
font_01_sfnt_off0000d6fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6FD 16620 bytes
SHA-256: 26225a8ae1a08d1329524137aaa223beaf438a29a1760a4d8a655b4cc3dc40c3
font_02_sfnt_off00010188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10188 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1