Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ecd9db9371aecea…

MALICIOUS

PDF

81.0 KB Created: 2021-09-19 18:04:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: da5d7cbd72e14849e96888af9d226c30 SHA-1: 707f86600a1756b4a8b65953c4e77a29fad0ebec SHA-256: 6ecd9db9371aecea56f01206054b48029a23fc07f83e8a6dea1b819d65ce8bb6
166 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing and trojan delivery mechanism. The heuristic 'SE_BROWSER_INSTALL_LURE' indicates the document attempts to socially engineer the user into installing malicious software by posing as a necessary browser update or extension. No scripts were extracted, but the PDF structure and embedded URLs suggest an attempt to redirect the user to malicious sites for payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://www.hkfew.org.hk/ckfinder/userfiles/files/xapum.pdf In PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/16145d44cbf805---19003086529.pdfIn PDF document text
    • http://jaatkinson.com/userimages/98662107165.pdfIn PDF document text
    • http://xaydungphongphu.com/uploads/files/fujemirukugapu.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161372abc86117---vorisejoxire.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/lijabizafugulemelixow.pdfIn PDF document text
    • http://satisfytech.com/ck/upload/files/45173948261.pdfIn PDF document text
    • https://afgventuregroup.com/cfiles/file/61800326147.pdfIn PDF document text
    • https://mentormedya.com/files/18740083687.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/89666113984.pdfIn PDF document text
    • https://editionsitaliques.com/userfiles/file/86712117058.pdfIn PDF document text
    • http://megamento.com/_UploadFile/Images/file/27197812919.pdfIn PDF document text
    • https://begili.com/uploads/image/files/makodugotadexojulodo.pdfIn PDF document text
    • http://thegioimaychaybo.com/app/webroot/uploads/files/98856633838.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/segew.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/32759398592.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/vukatuxavajogizu.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/40488250337.pdfIn PDF document text
    • http://doubler-son-capital.com/photos/files/90913470123.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/sotulunas.pdfIn PDF document text
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/kososuzebexa.pdfIn PDF document text
    • http://artkulinaria.pl/sites/default/files/file/nakex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=turkish+to+english+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_off0000d8dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F4 10772 bytes
SHA-256: fff467075f15cbc935bbcfa8ff7f6d95f22ff42109029062f50c1b3dff2d46c8
font_02_sfnt_off0001097a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1097A 17596 bytes
SHA-256: 93ddb894d2e0b3eeb677f9d558f91c8cd2d0ddbe6eecafc7fdbcd2145383c84f