Malicious PDF — malware analysis report

Static analysis result for SHA-256 eff7914324a1b941…

MALICIOUS

PDF

79.0 KB Created: 2021-09-19 10:37:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a66cfb1bcb6395384001a21daf4a1d66 SHA-1: 9f7cf868623a90e8a6900074546068415eaf7e2b SHA-256: eff7914324a1b9417c7841ddb01c61abd04c98760a3924e0bf74ec824d5f9318
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. It contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The PDF structure itself is also flagged for containing a large number of links on disposable hosting, further supporting the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://crysiq.ru/uplcv?utm_term=shadow+fight+2+mod+game PDF link annotation
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16146d8f43fb1a---sakamo.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/gowawoluwexijixifin.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/vesizokoxetufomagojeg.pdfIn PDF document text
    • http://bmfjhjk.friend-match.com/upload/files/94645214886.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/wofaxaxapejozaxa.pdfIn PDF document text
    • http://nieruchomosciklodzko.pl/files/file/javelo.pdfIn PDF document text
    • http://phunphu.com/userfiles/file/53191456460.pdfIn PDF document text
    • http://creationart.hu/files/file/mudufalirimefixurob.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/jijoxeviwutedapomitopir.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/33717675959.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/65451862557.pdfIn PDF document text
    • http://pumarecovery.com/userfiles/files/zowelekapogusofob.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/94755356490.pdfIn PDF document text
    • http://barcabianca.eu/upload/file/9809142400.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/lqg7jbv79ue8vhgaerslu2isp0/mazixup.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/5818234852.pdfIn PDF document text
    • https://lucky-erotic-massage-bucharest.ro/ckfinder/userfiles/files/85466594194.pdfIn PDF document text
    • http://vantaidongsaigon.com/uploads/files/76614356779.pdfIn PDF document text
    • https://sindicav.com.br/ckeditor/ckfinder/userfiles/files/54424814235.pdfIn PDF document text
    • http://eva.am/files/f9c7540623556844.pdfIn PDF document text
    • https://enilubricantvn.hoakhanh.vn/uploads/image/files/2060968904.pdfIn PDF document text
    • http://spzpoz-zdunskawola.pl/upload/file/wojimito.pdfIn PDF document text
    • https://wittnebel.dk/file/75133030583.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/nenukopo.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_off0000d386.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD386 10664 bytes
SHA-256: 47013cfd8501598232dcc393603308ed1c56ee03506271db1a095ccf1ea6f5d0
font_01_sfnt_off0000ebe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F8 16644 bytes
SHA-256: d9a576cfae0fc48c0832b5e6f77a87afd244f1e712afea0be43b5a1cdfc4bf80