Malicious PDF — malware analysis report

Static analysis result for SHA-256 53f936d31f51738c…

MALICIOUS

PDF

91.5 KB Created: 2021-07-13 21:05:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 762cd8996f2a3e987906c2904a6e3386 SHA-1: e330facf01c8226c14115d2b13103579e58ea446 SHA-256: 53f936d31f51738cf7149a3b6428d3ec5b7b5a2d3fe9ba174612a70095d271a0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file functions as a link farm, directing users to various external websites, many of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of numerous links on disposable or compromised hosting further supports a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://jejuecotech.com/ckupload/files/67441804980.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086a480f1b9c---35026895064.pdf
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/jh5vi148i0is9min3r1rah8ag7/paliwakigoj.pdf
    • http://diysmart.net/userfiles/file/bulebeva.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/189391935d98e26aa64384a900701ceb/karodalaju.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/2c27067eb38ce675d34b2d67a4204412/zazuze.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beef1dd8f63---12632002270.pdf
    • https://vicotelecom.vn/static/source/images/file/geweruzugekirekowusalozej.pdf
    • http://wtmongolia.com/materials/file/83376529576.pdf
    • https://nocenzura.space/web/img/podborky/files/64874797891.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a31e9814ad0---542925910.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/oe2o1o14krogbc7nue3pnlkb75/68135057496.pdf
    • http://yakutiaprime.ru/SITE/files/editor/file/jigusibi.pdf
    • http://armanetti.com/images/wuluwidojunefu.pdf
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/b91de015820da614e6c74b88f2bef714/zudotuganolawub.pdf
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/lfhir2orge50nblu19f5vp6fj3/zixuponubupeniruzazi.pdf
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/kijomiduxububoxije.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2caecc9ddc---8594284753.pdf
    • http://point-grey-1970-grads.com/clients/f/fe/fe7686cf254963525dc0bd811951f15e/File/lutimumiwatowosoma.pdf
    • http://springhs1988.com/clients/a/a7/a70db2535ed58991dd9724faf9b165d0/File/tugido.pdf
    • https://csn-alliance.com/data/files/5555845817.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=meaning+of+pitchy
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d5c1.bin
ea29c32384afcb37893abfb07894bdd3cf95776af30a58d131091dd9fc3012d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C1 2724 bytes
font_01_sfnt_off0000e15c.bin
f4e5dde69967fda56c29d4dad66a2111c2d2d7465a30c4a05e3374318dd2661e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE15C 17364 bytes
font_02_sfnt_off0000fa8b.bin
f110d8dc2130919ec8f17dfd0ac5a0ce99f63ab700b664b108ec697f578da46a
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8B 10552 bytes
font_03_sfnt_off0001128f.bin
f1236b3912f83e12f29fde61736a3c5ffb437292a13068552b1f1f3e2af66263
pdf-font-stream PDF embedded font (sfnt) at offset 0x1128F 20768 bytes
font_04_sfnt_off000146b1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x146B1 16792 bytes