Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7b2e7fadbbd93e1…

MALICIOUS

PDF

72.1 KB Created: 2021-09-18 04:50:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1aa8c10755a25fdafa73e6cfa9a031eb SHA-1: 2b0f25c037aee56ce4417621e10dd1847253ddcc SHA-256: c7b2e7fadbbd93e1941a760796910a70e0d882d12ad1b1e5c229bc4d6ef8dd3d
174 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. The 'SE_CLICKFIX' heuristic indicates the document likely instructs the user to press Win+R or paste a command, a common tactic to bypass macro restrictions and execute malicious code. The presence of numerous embedded URLs, many pointing to PDF files on potentially disposable domains, suggests a link farm designed to host and distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://aokisuper.com/ckfinder/userfiles/files/fugonatuxelifun.pdf In PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/nedexuvemakasugut.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210907205358.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/91831058908.pdfIn PDF document text
    • https://pulsekb.ru/admin/ckfinder/userfiles/files/wijobuwezixid.pdfIn PDF document text
    • http://hb-hospital.com/file_upload/fck_upfile/file/tiwuturiwenojurunojiliv.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d3fb32673---15122400873.pdfIn PDF document text
    • https://ukmalayalamnews.com/userfiles/file/89700551203.pdfIn PDF document text
    • https://kentacademymiango.com/userfiles/file/99521552722.pdfIn PDF document text
    • https://seeyounow.net/userfiles/file/70456651983.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/42781311375.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ab07cdd368---86689861331.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/rurezigokefozoremerosugo.pdfIn PDF document text
    • https://havadisname.com/upload/ckfinder/files/47983480765.pdfIn PDF document text
    • http://xn--brneneskontor-landsforening-b0c.dk/userfiles/file/tetodefuwibavovamejujopaz.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/lidelirijituwivesubo.pdfIn PDF document text
    • https://suavitinhtannha.net/upload/files/xalukisiruvu.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/dewokikor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=call+of+duty+modern+warfare+2+remastered+download+free+for+pcPDF 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_off0000b344.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB344 11140 bytes
SHA-256: 8074a757de0a82c34e3fa70eb01af01b7d90cade9845180386b8c2cd828c82ce
font_01_sfnt_off0000cd88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e59a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59A 17380 bytes
SHA-256: 26d39b4bc3a26cc5d94f324aa9b4acb6fdf4964e25ab3bfee4ec1278638c9c7b