Malicious PDF — malware analysis report

Static analysis result for SHA-256 c90bcbf3f0331cba…

MALICIOUS

PDF

72.0 KB Created: 2021-09-08 16:34:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 918b649ee19a97cccd4b689aa9a9e313 SHA-1: 347bb538d5b33d6f3fa58753954c9c783963102a SHA-256: c90bcbf3f0331cbae4b72baebf85622e64059c4bfe3947afa4ab02916551b405
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document contains numerous links to disposable hosting, suggesting an attempt to obscure malicious destinations. While no scripts were extracted, the document's structure and embedded URLs point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://sunmoon-glory.com/web/upload/files/49756765323.pdf In PDF document text
    • http://stensoproject.com/userfiles/files/ririrawalu.pdfIn PDF document text
    • https://egc.ecrom.work/syo/files/gatevakusanorovu.pdfIn PDF document text
    • https://aluminiosarla.com/userfiles_arla/files/kejifalirezo.pdfIn PDF document text
    • http://citty.org/images/uploads/file/10752045828.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161367ffccfb06---65017458982.pdfIn PDF document text
    • http://hiniceshine.com/upload/lisix.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/sakamikepevakuladez.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/18895624535.pdfIn PDF document text
    • https://albizy.com/ckfinder/userfiles/files/piwebi.pdfIn PDF document text
    • http://marcelponjee.nl/ponjeefiles/file/zifajumaxovoradugepe.pdfIn PDF document text
    • http://bettynblue.com/upload/fck_img/20210902/file/70535037918.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/95336194215.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/pijosusopa.pdfIn PDF document text
    • http://taxiluzern.ch/khurasan/userfiles/files/gijinuluxotovi.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/37463811510.pdfIn PDF document text
    • https://mangallagn.com/images/file/95216666017.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/50415544353.pdfIn PDF document text
    • http://www.centralperdana.com/file/30859818237.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210908121407_93218929.pdfIn PDF document text
    • http://lammensfilip.be/uploads/files/gukuzuradenuri.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/9459549629.pdfIn PDF document text
    • http://mywymc.com/userfiles/file/mijosolasoruzuxopijogasew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=free+kindergarten+pre+writing+worksheetsPDF 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_off0000b8e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0F2 15892 bytes
SHA-256: 1f549c787977c8aa14164720658316a9ca2009396e71f3f9ee0e863581306137
font_02_sfnt_off0000f971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF971 10780 bytes
SHA-256: 8e8eb38fb785c2ecf0e772084a5b75c3dba5d5f8fdf22c193b2e9267d6f44eb6