Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bba8aeb66de74ab…

MALICIOUS

PDF

80.5 KB Created: 2021-09-15 13:48:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: af3f79d1363737aa1c45b2703701c65e SHA-1: 1c8c87b9789a04b152b4aa2894ddbd585421ee63 SHA-256: 3bba8aeb66de74ab439589422380358778493993405e7d55a6ce1438df6616d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV detecting it as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm on disposable hosting. This suggests the primary purpose is to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://queure.ru/uplcv?utm_term=voice+changer+female+android PDF link annotation
    • https://mraos.com/web/userfiles/file/62808914232.pdfIn PDF document text
    • https://abss.pt/userfiles/file/wuzek.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210913191040.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/69860220115.pdfIn PDF document text
    • http://scarpatti.com/files/4224975377.pdfIn PDF document text
    • https://dcoderesearch.com/uploads/81192769496.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/57546003428.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613638696b9f0---nirawabupuradi.pdfIn PDF document text
    • http://euroear.eu/ckfinder/userfiles/files/38501309844.pdfIn PDF document text
    • https://successalpha.team/upload/files/74524385416.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/lomuwenogosotipesowal.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132de37cb3f9---79480348822.pdfIn PDF document text
    • http://dnepropress.net/files/file/27715074437.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/31950901176.pdfIn PDF document text
    • https://stauber.lt/images/files/lelozewuziruk.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/xesudeduwi.pdfIn PDF document text
    • http://vertracapital.com/uploads/files/lifodas.pdfIn PDF document text
    • http://pogologistics.com/ckfinder/userfiles/files/55138129020.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/zubenu.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c140eb4d8---77413886818.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/78402508687.pdfIn PDF document text
    • https://patc.fr/imagesfile/perodev.pdfIn PDF document text
    • http://mama-care.com/UserFiles/file/rejujamilesodip.pdfIn PDF document text
    • https://csam-villepinte.org/uploads/images/file/50843667540.pdfIn PDF document text
    • 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_off0000d8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A7 10628 bytes
SHA-256: 214ea6a8473a0ab7153cf5f600a5a946a62072394da2e6a660eca4d918099fd8
font_01_sfnt_off0000f085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF085 17196 bytes
SHA-256: cba3f1f712d025af764285ae96617e47d066ca69c6cbe98d219977eb8fba8d01
font_02_sfnt_off00011c91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C91 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1