Malicious PDF — malware analysis report

Static analysis result for SHA-256 771d6c3c14098373…

MALICIOUS

PDF

81.9 KB Created: 2021-09-09 10:50:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 687d50d17c3bbae1735007efa49a2164 SHA-1: 44c048de2c8ef6b40f958b2e4edb4e03c0375b94 SHA-256: 771d6c3c140983733a6f1d755b7e02563e75b4d357f5bb12b8b299d33b900145
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggest a link farm designed to redirect users to malicious content. The presence of 'utm_term' parameters in some URLs further supports a phishing or SEO-based distribution strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • 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://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613021d11e2cb---97706735989.pdf In PDF document text
    • http://hytechcommunications.com/userfiles/file/51105555381.pdfIn PDF document text
    • http://xsteelstock.com/d/files/9425517877.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/14aa2cc82351c3ca22c8b623c45dd971/mijov.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/89545303442.pdfIn PDF document text
    • http://cochemical.com/upload/files/50341349219.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///62091051450.pdfIn PDF document text
    • http://tomboy2.com/images/library/File/62437684749.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16138b4291200d---79591353433.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/ebaf70dc1cbe6c9a1e1822a3807ff061/53505563531.pdfIn PDF document text
    • http://topnotchimports.com/ckfinder/userfiles/files/fonosifuwitosuveze.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/46441318297.pdfIn PDF document text
    • https://cncunse.com/d/files/fawewelagosa.pdfIn PDF document text
    • http://equipociclistaugeraga.com/ciclistas/userfiles/file/74504928486.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354ddbdc146---folafimivawof.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136dc447abfa---97438492731.pdfIn PDF document text
    • https://jdrum-music.com/uploads/ckfiles/files/7663920841.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=fortnite+mods+ps4PDF 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_off0000ddb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB5 17848 bytes
SHA-256: fbca4ce593a70eb73a869548d955d9a97b687b05f3c0a72879a59b6ea8505a7a
font_01_sfnt_off00010b61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12378 10400 bytes
SHA-256: b7f4299fba4ee17dd70a1d140aa8024a25d1829863c02c2067ab42ba24a4a7f3