Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c3ffe88af1aa00f…

MALICIOUS

PDF

103.3 KB Created: 2021-09-01 18:11:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 6b61d4b22d45cfe847e211b6076441da SHA-1: b406deac203eb64824b82094d21a3a67cef90e19 SHA-256: 6c3ffe88af1aa00f75dc1ed16254c7166368ac955d20402d287b64ec21960ceb
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and other disposable hosting, likely to obscure the final malicious destination. The PDF's structure and the presence of multiple external links suggest an attempt to lure users to external content, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9425

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://tw-itemaos.com/ckfinder/userfiles/files/lorazu.pdf In PDF document text
    • http://dblbtech.com/userfiles/file/45423729078.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/r3omee0n4mpoj5kvb4padrh2ef/zabafeg.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/8c5dedbb044a88855799162c14b2ebfd/zuxipisar.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/kugubojurozefidili.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/30140651635.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/jitepinitazibinakofuno.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b95b270ed10---zusipazotitepipep.pdfIn PDF document text
    • http://mlead.net/images/e/file/zumikawirig.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/bagakiximosipiwaxitek.pdfIn PDF document text
    • http://kimhoatra.vn/upload/fckimagesfile/74739308727.pdfIn PDF document text
    • http://nw-line.ru/generic/uploaded/vususajeluvome.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/kitukapevofe.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/fakowaxivazagevuza.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/4f3b1e06163b170fb5f08cea99688755/55695914659.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/0fd5a7cba50c7b10ddea2c074a379873/66066363264.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea6e382e7b---ferinevifajiwok.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/32865893187.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0479636482---bajig.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/nalumiwejixiromatudiwiwew.pdfIn PDF document text
    • https://digireg.dk/upload/79010212850.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/96482765455.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=ffxiv+blue+mage+abilitiesPDF link annotation
    • 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_off00013b28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B28 10620 bytes
SHA-256: a784728a847e573691fbc57d4e43d2243f1daf7baaa77e36fc533629b48c6a46
font_01_sfnt_off00015382.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15382 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016b94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16B94 18440 bytes
SHA-256: ae248cd05e2836124cf20692f53048f48a81f1c84dd5d1513600986e89621fa6