Malicious PDF — malware analysis report

Static analysis result for SHA-256 a55bc507c019a57b…

MALICIOUS

PDF

71.5 KB Created: 2021-09-21 19:58:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c9b9178db010de23bbcf5df4a18a14a4 SHA-1: bac115bcbe82506e45dfbe3cfaf54ee392178a01 SHA-256: a55bc507c019a57bc8c646d20474638e4e782501d7c67d0aa09a800d656990fa
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of numerous external URIs and link farm heuristics points towards an attempt to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://pixomot.ru/uplcv?utm_term=wallpaper+android+green PDF link annotation
    • http://hzbmsj.net/images/upload/File/ruvukuvu.pdfIn PDF document text
    • http://laihoawedding.com/app/webroot/upload/files/62240324734.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/4d6cd9f52b3d39d225de56af606d62bf/tamukosudurofijaxipizirup.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161480f67ad413---jinozolabasixigavor.pdfIn PDF document text
    • http://dasbluemchen.com/pazatewe.pdfIn PDF document text
    • http://119pump.net/d/files/fujojezak.pdfIn PDF document text
    • http://novichiha.ru/pic/file/nabazidumukigonibuzoweki.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/gne1vvv2c1ns9ne2on9abnoktm/84124690767.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/fatemora.pdfIn PDF document text
    • http://thoitrangvabaoho.com/Images_upload/files/dogem.pdfIn PDF document text
    • http://agriturismoilnoceto.com/userfiles/files/2446693312.pdfIn PDF document text
    • https://oceanflowerhotel.com/uploads/image/files/86264593813.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/7ec7671c44f30b8f48a860cc05b1fe9b/51329877496.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/21d4affc835baddf952586de80921f02/ludew.pdfIn PDF document text
    • http://ekhoron21.mn/uploads/files/zewoxupamozijaz.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcc23785cf---30827443004.pdfIn PDF document text
    • http://zs-oilfieldequip.ru/d/files/xidinizotedeki.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/11928841851.pdfIn PDF document text
    • http://jeanthompson.nl/ckfinder/userfiles/files/9933611585.pdfIn PDF document text
    • https://bakwanudang.com/contents/files/vebonalew.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/zekedi.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_off0000b47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB47A 17204 bytes
SHA-256: f6474545dd43287bf0e4327f2b0bf5eeb68e3adc2463a7d86599486a75e9e403
font_01_sfnt_off0000e1d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D6 10292 bytes
SHA-256: 47bb23211423a4d1be4cbf99b4470489a5245b4ea84461dc066f431a2035f564
font_02_sfnt_off0000f8d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1