Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c0b2147c1fa0977…

MALICIOUS

PDF

79.8 KB Created: 2021-09-09 15:45:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c9362683c660507d17016854cb654c7e SHA-1: 0722be5a1a22aa51b36ac1c001d936697c1b778b SHA-256: 4c0b2147c1fa0977c4162694930eb28e8782b575d2bace6a9a4f0337b7771a9d
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous links to other PDF files, coupled with the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic, suggests a tactic to distribute malicious content or phish for information. Although no scripts were directly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • 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://sxcec.org/userfiles/file/57792214571.pdf In PDF document text
    • http://foto-klub.dk/userfiles/file/21059328631.pdfIn PDF document text
    • http://kenhuffbuilders.com/userfiles/file/79157867925.pdfIn PDF document text
    • https://tekdalyapi.com/upload/ckfinder/files/rerenasakuwudabonobaw.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/rofek.pdfIn PDF document text
    • https://nurdagihaber.com/resimler/files/24271606466.pdfIn PDF document text
    • http://flirdining.com/uploads/files/37328956218.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-2/20210902134633325519.pdfIn PDF document text
    • http://panziofabian.hu/fck_kepek/95015294948.pdfIn PDF document text
    • http://datacomsystems.cz/userfiles/file/jomebexojugoseza.pdfIn PDF document text
    • https://viveironativodevicosa.com.br/ckfinder/userfiles/files/37214021667.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/25531771687.pdfIn PDF document text
    • http://www.motionmantra.com/userfiles/files/56262758155.pdfIn PDF document text
    • http://pololanna.com/user_img/files/40856289622.pdfIn PDF document text
    • http://imailbox.nl/images/uploadedimages/file/moduvoguduxud.pdfIn PDF document text
    • https://coebmsf.com/userfiles/file/99134704264.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/2055153234.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-08/210908051506935329fh4zxswy3bof.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4dde460d5---31521614382.pdfIn PDF document text
    • https://desense.eu/uploads/wysiwyg/files/29735731085.pdfIn PDF document text
    • http://euskararenginkana.eus/files/galeria/files/80910464861.pdfIn PDF document text
    • http://edmo-cars.nl/images/file/xutozomafiweriwa.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/kibiwasiw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=neverwinter+nights+enhanced+edition+apkPDF 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_off0000d3f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC07 17016 bytes
SHA-256: 62b4f254bbab32e915997eb91e7e254bf25e272d1098f8fe58d42ae8cd27a3fd
font_02_sfnt_off00011868.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11868 10968 bytes
SHA-256: 730c15fedfec6e2851a40c47823f660207f6e591db323ac31537d1594b40a114