Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3d3f44c88406ea3…

MALICIOUS

PDF

85.7 KB Created: 2021-09-10 03:32:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 508cababaa7579b552c91e49b87e7e16 SHA-1: 052f716ad496727725752eb560e4a97af7a2b5ee SHA-256: c3d3f44c88406ea3bf3dcbcf60fd020a869578f469e113ed2e26b9d73f48e2bf
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a phishing or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://skyzoan.com/cake/beta/userfiles/file/96071930124.pdf In PDF document text
    • http://masterref.ru/editorfiles/file/66112962997.pdfIn PDF document text
    • https://derfo.info/resimler/files/bexalutubumixelitu.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613354722512e---nomujisedovotib.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/4812308737.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/sagadisilusasabarepug.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/5f396635fa16240ade6598fa115db4dc/66257543481.pdfIn PDF document text
    • http://k2plusinterior.com/userfiles/91932187227.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///202109082542_1008572379.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/2391837677.pdfIn PDF document text
    • http://chengzechem.com/upload/files/gefegemipetema.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/d457bd1ec7dbb63872cb8d494ea89a02/52087348267.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-3/20210903231243128997.pdfIn PDF document text
    • http://hvpeds.com/upload/contents/file/mataresenefejobepumo.pdfIn PDF document text
    • http://heatexchangersolution.com/upload_fck/file/2021-9-3/20210903154719763164.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/82373353503.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/55255844038.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210901123131.pdfIn PDF document text
    • http://pyramidplaster.com/file_media/file_image/file/13271682143.pdfIn PDF document text
    • http://geriatriccarenewjersey.com/userfiles/files/zasipuromegijisugudex.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/45695001398.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/gijowago.pdfIn PDF document text
    • http://sirmamedia.com/ckfinder/userfiles/files/77380650388.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=best+anti+mosquito+app+androidPDF 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_off0000e965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE965 10808 bytes
SHA-256: 49e3c0e5e2eb0dec68f2faaccf63edb9000880f8affe39027c59a72b6524bf57
font_01_sfnt_off00010214.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10214 18056 bytes
SHA-256: ea1fd9b373db41e343cbb00738ab9da977357add23e6a1d8cdfd00b40d799e15
font_02_sfnt_off000130f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1