Malicious PDF — malware analysis report

Static analysis result for SHA-256 a25a58db28145880…

MALICIOUS

PDF

97.4 KB Created: 2021-09-08 03:47:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 41fba6da2ad4c1542df9f0f4e48da4e7 SHA-1: ec1cff9653e56fd8b44c2a34732d30ebd7e45400 SHA-256: a25a58db281458809ee94c20dc14b2556308b9f37db26718e89c2295666d8966
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, indicating it's likely a phishing or malware distribution lure. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting an attempt to redirect users to malicious sites. The PDF structure itself is indicative of a link farm, designed to obscure the true destination of the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://dienlanhhuubinh.com/upload/files/jopulodadolefo.pdf In PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16072c36c68e88---2995761388.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/62f561af9bf1fa0abc44e372ab01bd4e/41686456332.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160e2a53979da3---lasaxadelebajirenijevi.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/sulofibipavaneraba.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/nukobedejesidisige.pdfIn PDF document text
    • http://poolprotektor.com/userfiles/file/56155401829.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/37838973205.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/xuwek.pdfIn PDF document text
    • http://www.patriarca-batiment.com/ressource/site-image/files/gijofotezegatuxum.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/40078886678.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/49079502657.pdfIn PDF document text
    • https://lentes123.com/aym_image/files/53233242323.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/daxudapevulepilufeba.pdfIn PDF document text
    • https://hotel-la-licorne.fr/userfiles/file/80176907381.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca7782decf6---909254218.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f723e5c29d8---31268283800.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/602d6363c32f93b544d5ea87bf5ac194/51609708364.pdfIn PDF document text
    • https://digireg.pl/upload/95592433697.pdfIn PDF document text
    • https://comfort8889.com/upload/files/duvavasepumadimijowukip.pdfIn PDF document text
    • http://carbonelite.ru/file/vototezomafovuge.pdfIn PDF document text
    • https://shopinhome.com/ci/userfiles/files/mamibirivedefori.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b2f23631c---67221556510.pdfIn PDF document text
    • http://matrix-corporation.com/upfiles/editor/files/fuwiluwivik.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/kexalozijezonun.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/of790skkpns4d07sg4u0rtnbfl/pulavopisosap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=child+psychological+development+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_off00011853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11853 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13065 17860 bytes
SHA-256: ae345295d420628d651d67b01f274cda282a9379962ae7e49a16015e80e21c9f
font_02_sfnt_off00015e40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15E40 11180 bytes
SHA-256: 662bc4ab1b10d35293d246ae8c3b8949604ab08c7bb5bf2ced1bdbee19d43c5e