Malicious PDF — malware analysis report

Static analysis result for SHA-256 c455cdd2ebcb92d8…

MALICIOUS

PDF

96.9 KB Created: 2021-06-28 17:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa443ea4eca09bea4a00c2d26d892407 SHA-1: f1d852815834b2b5da2c0d126e11c91059cde306 SHA-256: c455cdd2ebcb92d82892e3d465f4e15273e9c1fe81eca8b370fe620a9ffe9cfd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating it is a phishing or trojan delivery mechanism. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm or redirection strategy. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards an attack pattern involving the exploitation of PDF viewers to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.aluvascientific.com/UserFiles/file/folunop.pdf
    • http://westboroughhigh76.com/clients/b/bc/bc4984db1d461a603911d7e4814e3e59/File/355725343.pdf
    • http://luxe-pools.fr/i/File/bepufabogo.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160abb6728d489---60820803495.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609a09eba36b0---kumebukimomiv.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160747bb08feb8---kegeteweris.pdf
    • http://anthonyvienna.com/sites/default/files/file/tekusolipefesu.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3173ec6fbf---rixuxupadukolofubud.pdf
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/xewamanusejeji.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16074fbc4efa07---sijiwe.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/9675862615.pdf
    • http://cityhigh78.com/clients/2/2d/2ddbae4fb74c169819b3574d76e4e264/File/55673160196.pdf
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c508cde7a8---kinakowazomosotimudox.pdf
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/84r9g4od7ijkcn15cc83n4iv42/2661050457.pdf
    • http://rymwid-training.com/userfiles/file/95666369229.pdf
    • https://capital-tic.com/upload/ckfinder_temp/files/20210528210904.pdf
    • http://bukharasuwanee.com/sites/default/files/file/72803142302.pdf
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160878c1e9b113---73220278541.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8e36b4b4c---57531878149.pdf
    • http://pelesiuvalymas.lt/i/File/55811449908.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1607e53842115d---46343918137.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/5c3a549e5e5ebf4b0bde584590ee8010/28967909000.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/548ffdc8de6656d5e99d7bd6ff632d7e/79988912514.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160769d4d4cd91---82404951051.pdf
    • http://www.aadhar-interior.com/userfiles/file/puzekupafexure.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=seizure+of+power+meaning
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011573.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11573 16792 bytes
font_01_sfnt_off00012d8a.bin
855fe601a881f4791614d7f9934bff081423f66aa885c8242fa948200e5f72c6
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D8A 10712 bytes
font_02_sfnt_off0001463a.bin
f9b26fbc753763bef85e7a5a72fd7f9d1114185afbdb6aff90c6785d5f2354f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1463A 17832 bytes