Malicious PDF — malware analysis report

Static analysis result for SHA-256 900dad31b9b221ca…

MALICIOUS

PDF

76.3 KB Created: 2021-09-24 10:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 52627dc4d168c085cc9a2ea6a19e96b5 SHA-1: 9080c1efa74b5e7ee6a29a869983e889d77786a4 SHA-256: 900dad31b9b221ca09447772e22f8a48fa97ddc7327855fa85b15e0e8cc8faa5
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, with heuristics indicating it is a link farm on disposable hosting. The presence of multiple PDF links suggests an attempt to distribute malicious content or phish users. No scripts were extracted, but the PDF structure and URL patterns are consistent with malware distribution or phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161382892e6a60---fuzixoj.pdf
    • http://hexindechem.com/upload/files/30289020511.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/irte1alcthpkc0qokpdg7t2862/77045220444.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-9-24/20210924075942301319.pdf
    • http://zzzwchem.com/upload/files/87585041971.pdf
    • http://montesantangelo.it/files/files/zerajeminubejisozi.pdf
    • http://www.hgekc.com/media/userfiles/file/rotutapexekizutumetumo.pdf
    • http://saringkarnwood.com/UserFiles/file/3817671103.pdf
    • http://massimobertoarchitetto.com/userfiles/files/xetakopawuzinijevisudus.pdf
    • https://magiccat.pro/ckfinder/userfiles/files/95337739942.pdf
    • http://teplo76.ru/uploads/file/70288744606.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcebf54f24---vuwujipo.pdf
    • http://hiroi-es.info/yamituki-n/uploads/files/bilivuwine.pdf
    • http://bsinteriordesigner.com/userfiles/files/liselizuzukokeboj.pdf
    • https://nomortiga.com/contents/files/86923436294.pdf
    • http://sanyosushiglendora.com/uploads/files/2489243802.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/e78tlpg66jleh9n6q2kkkpl9tj/99867543649.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/26495450528.pdf
    • http://matras-devison.com/upload/file/6238828693.pdf
    • http://www.aragonemprendedor.com/userfiles/files/22257209975.pdf
    • http://circolonauticofavignana.it/userfiles/files/43391826649.pdf
    • http://firmen-bekleidung.at/userfiles/file/27276386150.pdf
    • https://tenderdiary.com/ckfinder/userfiles/files/pesuzilijigazoropumed.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=d%26d+3.5+planar+handbook
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c2a5.bin
b9ea38d099778c6b50b500b4bd3dfac6ed7d85ff2af92379d2a71515aaf27787
pdf-font-stream PDF embedded font (sfnt) at offset 0xC2A5 20888 bytes
font_01_sfnt_off0000f9be.bin
f695977626623e59fedb2fbedebd468d0acf89ff6f6ceafeb3cee4351ddee6c8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BE 9076 bytes
font_02_sfnt_off00010c63.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C63 16792 bytes