Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a3bae434bbfdbad…

MALICIOUS

PDF

84.9 KB Created: 2021-09-08 19:15:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3dfa20bed5bba1a1120a68fe98d392b9 SHA-1: c78097bae7af700e0849928891679cfad8b3dfc2 SHA-256: 8a3bae434bbfdbadcd1168095af3a6d61521c9f999568fb60a2a006c5c5ced4f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which are hosted on potentially disposable domains, suggesting a link farm or phishing operation. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating the PDF is designed to host many links on such domains. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://pavillonwohlen.ch/userfiles/files/vobituvugijufopizotirafi.pdf In PDF document text
    • http://www.serge-valentin.net/ckfinder/userfiles/files/50001240565.pdfIn PDF document text
    • https://dichvumoinoi.com/ckfinder/userfiles/files/jajelusujixozupu.pdfIn PDF document text
    • https://mvpartners.be/images/uploadedimages/file/rukugaleg.pdfIn PDF document text
    • https://luckysurface.itweald.com/uploads/files/6130d3234d80b.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16136c9dc14bf3---79381467242.pdfIn PDF document text
    • https://kingdomdatesuae.com/userfiles/files/bumelemepogefadoposune.pdfIn PDF document text
    • https://cam-ceeds.org/ckfinder/userfiles/files/nosemorogemimax.pdfIn PDF document text
    • https://laptopserwis.com/app/webroot/media/files/53036938886.pdfIn PDF document text
    • https://kcss.hu/korosi/userfiles/file/39741955909.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/41277536460.pdfIn PDF document text
    • https://kocarbonag.com/luutru/files/96698567036.pdfIn PDF document text
    • http://royalgroup.at/tmp/31893634130.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/jatiwexifanidenewano.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/rofetuxujalanemop.pdfIn PDF document text
    • https://xn--49st2et51duvk.com/upload/files/41157905130.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/657271990.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/72171553240.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/zitunosovo.pdfIn PDF document text
    • https://suativisamsungtaihanoi.net/upload/files/60271115611.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/fubozune.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/wavakemivofarujewi.pdfIn PDF document text
    • https://equipelec.fr/ckfinder/userfiles/files/86814271281.pdfIn PDF document text
    • http://cortabellanews.com/userimages/ribemopixidifawifetowi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=railway+map+pdf+downloadPDF 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_off0000e9f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F7 10408 bytes
SHA-256: f99a90a9b79c771ee4cd308537d0212b50d76ac0b74a4c21eebb44f2c30bb4e0
font_01_sfnt_off00010175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10175 17468 bytes
SHA-256: 0eae70e883c48b1c2df2d62c086d7981c165bc106b87fabd502fad5513c3541a
font_02_sfnt_off00012e35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1