Malicious PDF — malware analysis report

Static analysis result for SHA-256 8664c5de67c2143a…

MALICIOUS

PDF

78.9 KB Created: 2021-09-22 13:20:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e88083f3bf5c4eb7d1b5dcfc585bd5b7 SHA-1: dde0f6708edabc1a357826170f243c7c1a5280a6 SHA-256: 8664c5de67c2143ab9dc6bf594dc7f4d2434b418a50c7d207e58c9a81c94e43e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. Heuristics indicate this is a link farm, likely intended to redirect users to malicious sites. ClamAV detection and ML classification strongly suggest malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • 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.
  • 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://allytemp.ru/uplcv?utm_term=open+source+android+launchers PDF link annotation
    • https://gitteszoneklinik.dk/ckfinder/userfiles/files/mufozinidu.pdfIn PDF document text
    • http://skkl.cn/filespath/files/20210910205426.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/minigarefuzowikiwifuji.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/befobivik.pdfIn PDF document text
    • https://akanaymatbaa.com/calisma2/files/uploads/zifama.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/vopugavev.pdfIn PDF document text
    • http://vejwun.cz/images/44396465931.pdfIn PDF document text
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/94900910400.pdfIn PDF document text
    • http://xn----dtbhwhggdaoqfh3d.xn--p1ai/media/file/kitivemuvaro.pdfIn PDF document text
    • https://kimcert.net/E/file/32649403407.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/98618018435.pdfIn PDF document text
    • http://www.florentmaussion.net/userfiles/File/dolizuvatik.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/vojedumatirulufuvu.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/5d31c021a26d25b1826c15d0faafa760/69236520542.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/4t9it2njoljp1u3rv5snavg7e6/7038601870.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16146d9aca065f---vodoz.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/javebalujixoretor.pdfIn PDF document text
    • http://aromaonly1.com/yamituki-n/uploads/files/lixuleturina.pdfIn PDF document text
    • http://valentine.tutaylamhet.com/storage/ckfinder/files/dirivoz.pdfIn PDF document text
    • http://csc0898.com/userfiles/file/20210906133117_w5gsf9.pdfIn PDF document text
    • https://puntodeplacer.com/userfiles/file/72362226591.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/82242061489.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_off0000d35d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD35D 10640 bytes
SHA-256: 77cfb5de015652ea5a383fbf6624b14cfff14bc45c8c761a705ba70aacd739f9
font_01_sfnt_off0000eb94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB94 16620 bytes
SHA-256: 39d6e93768566843709cafa4ea13936e75930939761f5969cbb3c751ba7e7d22
font_02_sfnt_off00011652.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11652 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1