Malicious PDF — malware analysis report

Static analysis result for SHA-256 78a60a59a80e548a…

MALICIOUS

PDF

78.7 KB Created: 2021-09-20 13:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 72c86aba85820f6719ed6f6ed464e643 SHA-1: ec08e31520ba0eca2e7db587e6b1a2b6b64ea810 SHA-256: 78a60a59a80e548a6af9180389994c51667b3af1f029c7d7b3dde6ba88aa8929
126 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs pointing to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://mosallaesf.ir/uploads/ck/files/43571396584.pdf In PDF document text
    • http://gjbbang.com/userData/board/file/kagufivofuruvifopoz.pdfIn PDF document text
    • https://posetili.ru/userfiles/file/72288817501.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/24717412553.pdfIn PDF document text
    • http://delfosventures.eu/userfiles/files/71282650136.pdfIn PDF document text
    • http://scarpatti.com/files/dudukepo.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140aa32742f6---28580369657.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/nowerelo.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/35808356134.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/54565308205.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/bajalozidutopuwog.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/xaxiw.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/70120707478.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/92610028763.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/21812604145.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/85100369033.pdfIn PDF document text
    • http://szyoujin.com/UploadFile/file/20210903225327717.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-9-14/20210914022123375520.pdfIn PDF document text
    • https://xn----8sbcehyodmtf1czh.xn--p1ai/userfiles/file/11381480850.pdfIn PDF document text
    • http://at2apigroup3.com/contents/files/pirutebajanaba.pdfIn PDF document text
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/xavikofivolupazibi.pdfIn PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/ferifanifisovev.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/xofupatatemexafuridef.pdfIn PDF document text
    • http://ingmarcofaedi.com/userfiles/files/raviwapevisevimefew.pdfIn PDF document text
    • https://consultemergingmarkets.cubsindia.com/files/78859167279.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=anime+couple+wallpaper+for+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_off0000ce1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e62f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE62F 18224 bytes
SHA-256: c5862c55543a2af73de26cfd047a7f7c5b5393f7ecf610702973234e5507dedd
font_02_sfnt_off00011509.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11509 10680 bytes
SHA-256: 99667f5d45f4406c4e6b593f4d70e567641b7be26d3913e0ad515bea7a2b7293