Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2bbdb11c355ee27…

MALICIOUS

PDF

81.5 KB Created: 2021-09-14 08:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 94dcca53166c9b5a89bc6153c21a5ea0 SHA-1: c5cdd341191ae3c2fe362a01b610d7181af7d04a SHA-256: d2bbdb11c355ee273e8f020266ab8e79822fd734caaf40b765208eaad7508ed1
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common tactic to evade detection. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' suggests the document may be intended to trick users into downloading a password-protected archive, likely containing a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://the-bom.kr/upfile/files/56356778875.pdf In PDF document text
    • http://tcsklife.com/filespath/files/20210911011329.pdfIn PDF document text
    • http://karimeh.com/public/userfiles/file/7689845182.pdfIn PDF document text
    • http://logopeda-empatia.pl/content/file/nivawaralevunibufuzet.pdfIn PDF document text
    • http://ejmk.com/ej/upload/files/pekefusowutusinizanesoza.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/q3m04nepdqnfsn93issmta9prk/5997073613.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/netaxuperelofuxofifi.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/7205088234.pdfIn PDF document text
    • https://afma.pt/site/upload/file/88860298983.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/67004350200.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/rufif.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/53485366107.pdfIn PDF document text
    • https://leosservices.com/userfiles/file/22466315446.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/nekojozilunupij.pdfIn PDF document text
    • http://gusanhightec.com/userData/board/file/5768786053.pdfIn PDF document text
    • https://baigiangtoanhoc.com/upload/files/6159065113.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents/files/zapevidukun.pdfIn PDF document text
    • https://pottoka.info/files/galeria/files/vadefo.pdfIn PDF document text
    • http://seamcc.com/UserFiles/files/jesadamiludadosupu.pdfIn PDF document text
    • http://malifer.hu/upload/file/koguxokodezurirovubewe.pdfIn PDF document text
    • http://paroissedementon.fr/upload/files/87046391806.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/wadabuno.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/51974320888.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/rumajojediz.pdfIn PDF document text
    • http://denda.co.kr/ckfinder/userfiles/files/48878329858.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613c74999a751---12617707874.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+lock+location+on+androidPDF 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_off0000dd19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF530 10232 bytes
SHA-256: 867f19af841748d93af0de032dd46087c6a3fbb3af3afacc6150635c0fafa600
font_02_sfnt_off00010c3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C3F 16892 bytes
SHA-256: 3bb816022e60eb25589cff2dc9dff9f517df04d89b2369c75adc37a17966b93b