Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5907bcf904850bc…

MALICIOUS

PDF

71.3 KB Created: 2021-09-27 15:10:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 66de51c0a50c121ac0a200c9f986c4fd SHA-1: eeda43271868869b1df46264d1cd3e2c0d478f38 SHA-256: a5907bcf904850bc2b9f4169a75d2c5444cb2a8d5802a5724f0bd153f367bb03
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, exhibiting characteristics of a link farm. It contains numerous embedded URLs pointing to other PDF files hosted on distinct, potentially disposable domains. This suggests a tactic to distribute malicious content or lead users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://mylivediamondinventory.com/uploads/files/mofododixogijotimekora.pdf In PDF document text
    • http://freestyler.cz/img/file/dalowez.pdfIn PDF document text
    • http://santabruna.cl/upload/file/30808847509.pdfIn PDF document text
    • http://vitalbafitnessclub.eu/userfiles/files/11109312137.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/35038953840.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/78110332912.pdfIn PDF document text
    • https://lordoptika.hu/files/files/91726625104.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/20990056064.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/b98435ab06a974f61b9548d3e6bb84f4/17627860765.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/37548714402.pdfIn PDF document text
    • https://jnnjhansi.com/userfiles/file/matanirazopemuwisovosoja.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/23821159754.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/87984745774.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/50332893519.pdfIn PDF document text
    • http://naturalwonders.com/uploads/files/95418440571.pdfIn PDF document text
    • http://soundspace.eu/Upload/file/wowim.pdfIn PDF document text
    • http://www.taimaobi.com/admin/ckfinder/userfiles/files/wamunotopazabagorole.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210914_5F0B1A1AD3E33E49.pdfIn PDF document text
    • http://boq.internet-match.com/upload/files/63671200083.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/91917578076.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/84490586970.pdfIn PDF document text
    • http://poorclarescork.ie/images/86026960436.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1631359105.pdfIn PDF document text
    • http://pro-customer.de/userfiles/file/87071266301.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/54910e1ac6720e301d1729992edfc156/24254165919.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/15672349605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=present+continuous+exercises+pdf+primaryPDF 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_off0000b475.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB475 11052 bytes
SHA-256: 5db4b2bad4fc9b1838515b4550719da3ee306b2d797a84b06beb897b5fee18dd
font_01_sfnt_off0000ce45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE45 16016 bytes
SHA-256: 8c3bbc7c18f79838d804fd409e4b15ecb789cd2cb2b9cd16f453ff97c87d25f9
font_02_sfnt_off0000f6eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1