Malicious PDF — malware analysis report

Static analysis result for SHA-256 c05df688128a36bb…

MALICIOUS

PDF

88.3 KB Created: 2021-08-21 07:18:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0b10313918859b13a772566526801fe SHA-1: 32f369c842958d12829b3659aa111dbde1e196d5 SHA-256: c05df688128a36bb864d17f69c1358ec9dcb55bfd0c96a897ffd8ff565e071be
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised CMS uploads and disposable hosting, suggesting it's part of a link farm designed to redirect users to malicious sites. The presence of external URIs and compromised upload links strongly suggests an attempt to exploit users by directing them to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://master-sign.ru/ckfinder/userfiles/files/30707133969.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb419ada7bc---zepunepet.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16093d3c056601---19775660992.pdf
    • http://phannhan.vn/files/usersfiles/files/jiliwobefijikusefeguper.pdf
    • https://markmont.eu/editor_uploads/system/files/fazukodiwafipoturegasa.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/q748dkftbaf4gd0ibkekoqha9b/wezemudakizufetogavijus.pdf
    • https://aimtronu.org/userfiles/file/65870106112.pdf
    • https://perfecthospital.org/FCKeditor/file/xupisegojapipitonupopoxel.pdf
    • http://www.anclupnapoli.it/userfiles/file/ranofidebobili.pdf
    • http://benetworkingpro.com/ckfinder/userfiles/files/susuvodipijo.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16078d11922f6d---11083756019.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/74c3f186c9ed5c09d46b7e1629420ae0/xudikexu.pdf
    • http://dobre-jaja.com/Upload/file/lemiwifumadigilabuveguzuj.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee303b52159---nisegum.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a94e412ee86---96488833782.pdf
    • https://toskov-yordanov.com/userfiles/file/vufumibezotudisawon.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/vked92hqbhlrq2de5njuq3q2b9/35515054198.pdf
    • https://egyiksem.hu/uploads/file/finugariferoteripukob.pdf
    • https://atcotourismtravel.com/userfiles/file/solakupekerunibo.pdf
    • https://jbdclothiers.net/emailer/userfiles/file/13918490834.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/7adb8c5d375dae1a2405bd505d188cc0/3249909540.pdf
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/e36cbpeg9kusk0fbu6r7noqohb/71456697569.pdf
    • https://netshopnepal.com/userfiles/file/14130951809.pdf
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/botafivejelugivenewu.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e9a542d23---85489520558.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=where+did+gunpowder+originate+from
    • 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_off0000f297.bin
2e31522de4c5d398b7ecb4445c7ddf81ee4a04d1bdd38c142f300aecd20a06b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF297 10912 bytes
font_01_sfnt_off00010b7e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B7E 16792 bytes
font_02_sfnt_off00012390.bin
0555a4f66cf8bc287065f9d52701d5eef8f2543e91c3bf4814104e370db7c954
pdf-font-stream PDF embedded font (sfnt) at offset 0x12390 17660 bytes