Malicious PDF — malware analysis report

Static analysis result for SHA-256 307a4f0b556cdbf5…

MALICIOUS

PDF

86.0 KB Created: 2021-09-19 10:49:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1951c7a6a85bb35a538808cb5ffdde16 SHA-1: 353fd4bf1295b8f01b11a27cb8c65cdc2063ff9c SHA-256: 307a4f0b556cdbf59ffb935c221097d2d13fc725344f2a3fadb1d6915c82ff65
126 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable hosting and using UTM parameters, strongly suggests a phishing or link-farming attack pattern. The document body was unreadable, but the heuristics and URLs are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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=breadboard+simulator+android PDF link annotation
    • https://eseninternational.com/uploads/files/29295189610.pdfIn PDF document text
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/bilod.pdfIn PDF document text
    • https://allcondosales.rodeodrivecondosale.com/userfiles/files/67579069071.pdfIn PDF document text
    • http://easy-sleep24.de/shop/images/editorfiles/file/83083626124.pdfIn PDF document text
    • https://scout-educationguide.com/userfiles/file/32351813961.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/nidoperudaguxajo.pdfIn PDF document text
    • https://tramhuonghanoi.vn/upload/files/23409450187.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/30397398512.pdfIn PDF document text
    • http://svsteinfurth.de/radsportfiles/file/rujowolafuvodajeluwasu.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/gosudabumelelusam.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/86330827579.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/2cdbae3c8ac34b7c8d16f9403b598eef/2903925358.pdfIn PDF document text
    • http://liyangah.com/Upload/file/sinodazuxoj.pdfIn PDF document text
    • http://siblom.ru/files/upload/file/zomapoxabukumujokigenogi.pdfIn PDF document text
    • http://minhphucvietnam.com/uploads/userfiles/file/jotorozeworomipubojadesaj.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/7933785468.pdfIn PDF document text
    • https://incoyun.com/calisma2/files/uploads/sotom.pdfIn PDF document text
    • http://fatimaartwork.com/userfiles/file/46883788645.pdfIn PDF document text
    • http://abcbyspu.net/ckfinder/images_store/files/bulijogaxogolofuxisiroref.pdfIn PDF document text
    • http://dreamsurgerycn.com/ckupload/files/lopifimulapatefuvasomi.pdfIn PDF document text
    • http://ph-easycome.com/userfiles/file/bakufinurapimek.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4eb83378d---koralitagovu.pdfIn PDF document text
    • https://malinaionescu.ro/userfiles/file/zitokogojonodotezefepivov.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/96897317317.pdfIn PDF document text
    • https://kiofruits.com/admin/uploads/files/38760852295.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_off0000e87f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87F 19036 bytes
SHA-256: 6c0fdcaabfb817236e78ae68bfe105c9f757f726a012cf33c54df4fb3fb36407
font_01_sfnt_off000119a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131B7 10704 bytes
SHA-256: 32cb27675f6ec0bd0cb77594478448a1fdc1f3ce51817ad3fae0ee942db916d7