Malicious PDF — malware analysis report

Static analysis result for SHA-256 7156a2044663648b…

MALICIOUS

PDF

76.1 KB Created: 2021-09-14 09:12:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 08f3850f61cb4df8008cee7c1cec09bb SHA-1: 7adecb6ac5c52ba3dc979c11dd97e4c04d204ef4 SHA-256: 7156a2044663648bc3e210b1f89ac274c3f8e6417342e2d4bed40d836fe99d66
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to multiple disposable hosting sites. The embedded URLs, such as 'https://catamma.ru/uplcv?utm_term=how+to+recover+data+from+mi+phone+after+factory+reset', likely serve as lures for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://catamma.ru/uplcv?utm_term=how+to+recover+data+from+mi+phone+after+factory+reset PDF link annotation
    • http://ayurvedicclinic.org/userfiles/file/11380594415.pdfIn PDF document text
    • http://www.cenlafilm.com/siteuploads/editorimg/file/zozizederifanewa.pdfIn PDF document text
    • https://melz-feu.ru/upload/61203947061.pdfIn PDF document text
    • http://bbu.vn/Images_upload/files/30563468800.pdfIn PDF document text
    • https://valenciamaids.com/userfiles/files/roranolebipukegojin.pdfIn PDF document text
    • http://geometramaurotozzi.it/userfiles/files/rirosagike.pdfIn PDF document text
    • https://ijaetis.org/ckfinder/userfiles/files/zemafibozomiz.pdfIn PDF document text
    • https://tskrea.com/userfiles/file/figirinativo.pdfIn PDF document text
    • http://kiajihlava.cz/UserFiles/File/94017078608.pdfIn PDF document text
    • https://tuinvandecruys.be/file/49414044026.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/tepebe.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/rekewerakefedumobeg.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/jujosoris.pdfIn PDF document text
    • http://ruben.pl/ckfinder/userfiles/files/kafibo.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/viguwulakuloxafokif.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/88680433230.pdfIn PDF document text
    • http://cyc.cz/pictures/clanky/files/kijoboxupafaxe.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613672c574dcb---93869806771.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///posajojeturufavu.pdfIn PDF document text
    • https://divanich96.ru/admin/ckfinder/userfiles/files/27125583739.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/xegigunu.pdfIn PDF document text
    • http://czyxchem.com/upload/files/79645146532.pdfIn PDF document text
    • http://myarrahnu.com/mo_images/files/98709978115.pdfIn PDF document text
    • 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_off0000c3c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3C1 11096 bytes
SHA-256: 0dad9255bc2b07857d06956c410cfad60d13c711c4c5401a5a725f2ae345e562
font_01_sfnt_off0000dd77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD77 17436 bytes
SHA-256: b44a3b8cd9df03c8ace528fca31c132ff99ac1f3c896b21f5531ec002f47810b
font_02_sfnt_off00010a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1