Malicious PDF — malware analysis report

Static analysis result for SHA-256 e0258565349bd3f8…

MALICIOUS

PDF

79.3 KB Created: 2021-09-22 14:01:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5edebe1d7a4fb0e54400027b20e5a45c SHA-1: 4ade746038287c3236bd157a5ed46db7c64bec47 SHA-256: e0258565349bd3f825035400bc1fa27bcaff6de2891bc1e1da1ec501858d260a
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of numerous unknown URLs suggests an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://kirakuramen.com/uploads/files/toxixelekarurajuko.pdf In PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/84275920286.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/49245729438.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/wujola.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/xazabebejesadanuvo.pdfIn PDF document text
    • http://ruben.pl/ckfinder/userfiles/files/marevipovinonu.pdfIn PDF document text
    • https://goooinggroup.com/userfiles/files/20210918_232017.pdfIn PDF document text
    • https://saigonservices.vn/images/uploads/files/pebupunufep.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614232b3eb093---49680042544.pdfIn PDF document text
    • http://xn----8sbfhu6ab4bqv.xn--p1ai/userfiles/file/nukeraforulagu.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/48919364361.pdfIn PDF document text
    • http://synphabase.ch/upload/file/vifafaruguruwepuxaju.pdfIn PDF document text
    • http://mt-filtration.com/uploaded/file/145876610561471dd17469a.pdfIn PDF document text
    • https://helicopterleasingservices.com/userfiles/files/75615339384.pdfIn PDF document text
    • https://oancora.com/ckfinder/files/21746311390.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/nikap.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/bl6815kagg1ofbogo7jgtp76g0/basipomigupux.pdfIn PDF document text
    • http://ansonseatery.com/uploads/files/mijeredonimudumi.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/kamamole.pdfIn PDF document text
    • https://pasarangroup1.com/contents/files/jilotupobiv.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/58835963180.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16144f9ccedf09---67823243008.pdfIn PDF document text
    • http://www.farmaciapenil.es/userfiles/files/7525875251.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=square+root+of+complex+number+formulaPDF 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_off0000ce79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE79 10944 bytes
SHA-256: 3b2e8f8ee84d9fb7e457f3afbadb818caa3e775c3b2254ba79124f30673852ef
font_01_sfnt_off0000e7a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A8 18596 bytes
SHA-256: a80fb9fe8815e70d6019f3a496fabedd33b7da620e6caa5805756fb04a2866e1
font_02_sfnt_off000117a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1