Malicious PDF — malware analysis report

Static analysis result for SHA-256 b80665aaa1975c3d…

MALICIOUS

PDF

87.0 KB Created: 2021-09-09 16:30:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3c04a31a483894bf412c925b12eefa19 SHA-1: 9d263d047ec45cf986250ef2d1c1b05cb8c4926b SHA-256: b80665aaa1975c3d178459d58cad8665638bafa2865b6e362479bd94687f6613
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous embedded URLs that point to disposable hosting, suggesting a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically identifies this pattern. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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=how+can+i+use+my+firestick+without+the+remote PDF link annotation
    • http://ensky-chemical.com/upload/files/nepolexudowesatude.pdfIn PDF document text
    • http://aurora-c.jp/files/files/dumeramubunisitepuvojut.pdfIn PDF document text
    • http://zhatuogz.com/uploadfile/file/keforizenabewam.pdfIn PDF document text
    • http://dichvu12h.net/userfiles/file/ruguzugawutesosilax.pdfIn PDF document text
    • http://samocvet.org/foto/ck/files/betipaxuboxitubekijufo.pdfIn PDF document text
    • https://premiersuli.hu/files/files/vaviwimofesawexurajanijo.pdfIn PDF document text
    • http://bbfederico2.net/userfiles/file/pipirakelu.pdfIn PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/japetete.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/bixifetekefipataj.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/52064799452.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/22525836124.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/rivajixawijanip.pdfIn PDF document text
    • http://alexdisinfestazioni.com/userfiles/files/94339993473.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/tegosob.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/rifofutosuwowafox.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/103703196616a1221640cefe21bbab38/96324502139.pdfIn PDF document text
    • https://kanalprofi.at/UserFiles/file/danimisigopasefupego.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/22803234299.pdfIn PDF document text
    • http://camonetinternational.com/files/file/42253378582.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021932014355364.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/16131587685709---xarukatuzatosogofag.pdfIn PDF document text
    • https://haciendaloscipreses.cl/upload/file/wopazomir.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/bebasusiwip.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_off0000eb83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB83 18816 bytes
SHA-256: 5a6553c029c34e4d948386de25c80aafa75b994ee21a3ada6bd034fd99d4f170
font_01_sfnt_off00011cb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB6 10936 bytes
SHA-256: 69950ddbcf05ae6b490930feda4ce89504a5d7664ecf3a8ff83db98f6e3568d8
font_02_sfnt_off000135f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1