Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8c97835aea5d064…

MALICIOUS

PDF

78.0 KB Created: 2021-09-05 01:31:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 199f736697f1987b5b1b96fb80015fb8 SHA-1: e8c1270384faae63e86189d94d17a552863502bf SHA-256: c8c97835aea5d064609eaaf49bcf9cdd35ada08268ac534315519963fb458491
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://fine-cottage.ru/userfiles/files/22753264370.pdf In PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f16a6cac3.pdfIn PDF document text
    • http://atreve.eu/ubezpiecz/obrazy/file/tofopijedazelidisejikoz.pdfIn PDF document text
    • https://almondzwealth.com/administrator/imagetemp/file/6230634228.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/19d4db3e457f2ca008a0fb96c7704d05/7868272779.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611d928d1cafc---30308751649.pdfIn PDF document text
    • http://alkanboya.com/files/file///31711960295.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/gegamosonubipud.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/lanuw.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/4ecfd6ad79d02aee3a1e19df571a847a/25188170258.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/resatejifidikofegilaxevut.pdfIn PDF document text
    • http://thegioituigiay.net/uploads/files/78545634776.pdfIn PDF document text
    • http://amandamaitland.com/images/file/pawenogele.pdfIn PDF document text
    • http://debden.org/userfiles/file/najumabenetebofenore.pdfIn PDF document text
    • http://thietbibepnhahang.net/media/files/wipik.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607475009fb0e---12162721035.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/983816d430b1b5f202c111007c585735/77231476443.pdfIn PDF document text
    • http://bydnjl.com/userfiles/files/gesezuxojebiguba.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16091a9461830a---8161729928.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/24251459681.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/f18851fefbd0fbd74c091be5b2bac4fc/kamamozutigamivedifenare.pdfIn PDF document text
    • http://massintech.ru/img/outer/files/16215786127.pdfIn PDF document text
    • http://jimmartinfamilyreunion.com/clients/35696/File/65439772552.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dcd51ec07d8---9271288511.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=scosche+gm2000sw+pdfPDF link annotation
    • 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_off0000c8e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e0fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0FA 10868 bytes
SHA-256: 139631cbe7d0bf99c1c57624a36d9aee8e4649d8d002c75cdcfb64eafc065fae
font_02_sfnt_off0000f9f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F4 18612 bytes
SHA-256: 1aa676119dab682d621c78530b64c1be65ea00864dce9f8172dc31e15839d1f7