Malicious PDF — malware analysis report

Static analysis result for SHA-256 09c8b591ae33d474…

MALICIOUS

PDF

73.0 KB Created: 2021-09-09 08:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c687582a151f3db39628f7201f0dc646 SHA-1: 852b1938c132d6fbc06fda8f434ffca0203f91b6 SHA-256: 09c8b591ae33d47455d4550521587ce94eaafe17e46aac3b9409098618e9e4a5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://cructi.ru/uplcv?utm_term=how+to+generate+apk+file+in+flutter PDF link annotation
    • http://tradotel-riviera.com/file/xejabikitozidiboj.pdfIn PDF document text
    • http://ucokampen.com/media/files/10295719208.pdfIn PDF document text
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/53182430716.pdfIn PDF document text
    • http://www.como-grup.ro/fisiere/file/12289008061.pdfIn PDF document text
    • https://xuanhongkhang.com/upload/files/wuzalesemelusawawoser.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/migoxozunebezezonuximusaw.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/tatimigiwazemugodipuzek.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/5403555707.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/nelijafadibal.pdfIn PDF document text
    • http://www.kingsmen-cmti.com/upload/files/38370543766.pdfIn PDF document text
    • https://ibrahimkoc.com/images/Media/files/zirunulexezovi.pdfIn PDF document text
    • https://delta-relay.be/userfiles/file/besisul.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/25153313475.pdfIn PDF document text
    • http://quaisetoiles.fr/img_pages/file/28457974652.pdfIn PDF document text
    • http://stroytehcentr.ru/images/file/20895461725.pdfIn PDF document text
    • https://easy2ticket.com/upload/files/33169062122.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/digiwasof.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/bf49154f6820c7ac9ff98cf7226af7db/34432447155.pdfIn PDF document text
    • https://tatsolarlight.com/uploads/files/92613735461.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/161318e760b412---molixirilugojemobijixa.pdfIn PDF document text
    • http://www.heatandgas.com/EditorImages/file/67292168768.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f94ad00dbe---8170385624.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/bokekelikizoxupenixojuf.pdfIn PDF document text
    • http://nenayu.com/filespath/files/20210905013157.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_off0000b7b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7B5 10632 bytes
SHA-256: 1bef60b8b19fed42116049249b445bc24ed9f6a92ee955dacc0c5a2a6ff6c211
font_01_sfnt_off0000d028.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD028 17244 bytes
SHA-256: 5d6fc5b98d6bc7a93a5f550ca1368aa2eb1280801ef898cf73301a03b3f95167
font_02_sfnt_off0000fce6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1