Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d291890f435cd9e…

MALICIOUS

PDF

81.1 KB Created: 2021-09-18 14:12:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7c43e33ccda86cfe0499b49f08272b90 SHA-1: c67e1a7d26c32f37903c2f62595a42651f30eb99 SHA-256: 8d291890f435cd9e0caba22416513723490df7f8c190b90842349f6e3820e57b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many of which appear to be compromised or disposable hosting, designed to host further malicious files. The presence of a 'download button' heuristic and the ClamAV detection strongly suggest a phishing or malware distribution attempt. The ML classifier also flagged this PDF with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 https://oniceh.ru/uplcv?utm_term=windows+7+iso+32+bit+file+download PDF link annotation
    • https://stradatextiles.com/upload/ckfinder/files/39304661449.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301cc7d0767---gatinepedepapojewi.pdfIn PDF document text
    • http://islenapuntos.com/campannas/file/77366453060.pdfIn PDF document text
    • http://secoinblock.com/upload/files/45028749727.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/gomelefijurunetedevu.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/vokizalosofirivutujisurid.pdfIn PDF document text
    • http://khocabien.com/uploads/files/xajiwifijuruzuv.pdfIn PDF document text
    • https://ferdavagnar.is/images/fck/file/62664649607.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/demijikepid.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/tugagopetezotazipov.pdfIn PDF document text
    • http://ajk-opakowania.eu/upload/fck/file/92620067499.pdfIn PDF document text
    • https://melz-feu.ru/upload/suvevizosid.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133cfb3b9c04---juxoromiwozokezejiwebeg.pdfIn PDF document text
    • https://aldaserwis.pl/ckfinder/userfiles/files/zezasajusatefibon.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/rikos.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec18addd26---jugoketudokomadesuveno.pdfIn PDF document text
    • http://ediljolli.com/userfiles/files/15669691538.pdfIn PDF document text
    • http://automyjka.pl/automyjka.pl/userfiles/file/60674086713.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/88002127787.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614223c9ac095---71635294823.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/34447422152.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_off0000d587.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD587 18560 bytes
SHA-256: 80c9faf103715670a4c3d1fc2573efc6def4c7385926ac264d78393fc06774b1
font_01_sfnt_off0001059d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1059D 10808 bytes
SHA-256: 397ffc8791414176d5f74a62f7a4ae639b4bea03cc14548c70a82b5c394e332f
font_02_sfnt_off00011ed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1