Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f88ee93ccae5ab4…

MALICIOUS

PDF

79.0 KB Created: 2021-08-25 13:35:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8b89a64577bb05ab9e7003e0351f5659 SHA-1: ec8a73f226e017717d8f223ded9cf31abfcb1aa3 SHA-256: 2f88ee93ccae5ab4ea5934c824d992627e607ad4f34d4b9a0a0a70c53555a458
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, indicating it is likely a phishing or malware distribution lure. Heuristics indicate the PDF acts as a link farm, directing users to multiple compromised or disposable hosting sites. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6941

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://smidgel.ru/uplcv?utm_term=high+dielectric+constant PDF link annotation
    • http://pngroup.pl/ckfinder/userfiles/files/60255503220.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/lutusujo.pdfIn PDF document text
    • https://weddingitaly.jp/images/file/2395808418.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/udq7th63okntd73jsp2h6a4sec/teduvilig.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/72995562841.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/12285458003.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/rubow.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af6a7d3c6ec---48633530288.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/bitekojebajolufaxunapexo.pdfIn PDF document text
    • http://starwindows.ie/ckfinder/userfiles/files/71390285020.pdfIn PDF document text
    • http://peak-experience-japan.com/images/blog//file/3894389783.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/31144230242.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16098a53c42560---56896432116.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/6559679ba0d4a0d83d0d8d1d958b1d1b/dotaxedesikefunaja.pdfIn PDF document text
    • http://westpakusa.com/phpsites/vertical_living/uploads/file/66151421684.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/m94jkinsrpqc74d6etr56uijai/kizojazofoxikulolemid.pdfIn PDF document text
    • https://cuichi177.com/uploads/files/202108171902493826.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/o5cooouuh2j7pms69eis13b8u8/2219139404.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/8d52d52fb4df5d35c29570c050970d30/44924272983.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///kudukuxoxamibu.pdfIn PDF document text
    • http://burragebrothers.org/demo/jolie/beta/userfiles/files/jepumowakotasuget.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/86421578655.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/0b238a041bdef01d4d0d0315c2969e9f/noveje.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/16083a2e1c685d---13201164053.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7541e1241e---14212231333.pdfIn 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_off0000dae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FF 10640 bytes
SHA-256: dbd120e09d520f6c2f556e0dc77ae7bab6a383f7cbd3eceaf101d8ea90218804
font_02_sfnt_off00010b03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B03 17304 bytes
SHA-256: e72223bcb3f3a757971162dc1960c44b522ea1e83d3141c126b917cf9aee525f