Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4fcad4b17ea7ec8…

MALICIOUS

PDF

74.8 KB Created: 2021-09-12 16:02:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3c6011cebcd96603bdb8f80ce08fe64b SHA-1: a33dec570118b58f43ef2cc594b47b6d60a175b1 SHA-256: f4fcad4b17ea7ec86f939a1e92b0976f92b745c4837979ba540a0333c08aadcd
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to various domains, many of which are configured as link farms with UTM parameters, suggesting a phishing or malware distribution campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags the document's structure as a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://huntic.ru/uplcv?utm_term=game+game+chahie+game PDF link annotation
    • https://coopinproject.eu/ckfinder/userfiles/files/kilop.pdfIn PDF document text
    • https://al-wesam.com/userfiles/files/96117108506.pdfIn PDF document text
    • http://soles2walk.com/data/file/75171634741.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/xusonumijiv.pdfIn PDF document text
    • http://moristas.com/userfiles/files/51220628044.pdfIn PDF document text
    • http://used-machinetools.ro/app/webroot/files/userfiles/files/85344893094.pdfIn PDF document text
    • http://ebonit.light.bg/includes/libs/ckfinder/userfiles/files/migijogelawonuwiwip.pdfIn PDF document text
    • https://gites-les-bardots.com/userfiles/file/wapewoxiwexum.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/31467705380.pdfIn PDF document text
    • http://yoron.net/up/files/kemuwuwujegimelu.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/tuweruboxo.pdfIn PDF document text
    • http://achilleferolla.it/userfiles/files/19462631014.pdfIn PDF document text
    • http://udaybharat.in/ckfinder/userfiles/files/50803083904.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/boluselatozupumuzogu.pdfIn PDF document text
    • https://projektovanje.info/userfiles/file/tuzofu.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/37820602754.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/161301c3745a30---90967912786.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7a3049820---doxojuzo.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/96976752754.pdfIn PDF document text
    • https://wecareprogram.org/images/file/56538452684.pdfIn PDF document text
    • https://whitepalacegrill.com/userfiles/petiwivonimuvuvepabuf.pdfIn PDF document text
    • http://stonebreaker.at/7742000085.pdfIn PDF document text
    • http://pizzeriagiganti.ro/imagini_ws/77412300414.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/62271295052.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_off0000c4a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4A1 16640 bytes
SHA-256: 5c66283a6848cfa2c74675023424c6eaff39586e49b0d5d1abbcdd2b305afe28
font_01_sfnt_off0000ef6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF6B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010782.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10782 10080 bytes
SHA-256: 9964b1158ec08b0caec08ae027503d5add627729a0742e361b69b0e2758a1417