Malicious PDF — malware analysis report

Static analysis result for SHA-256 8955f164ec223885…

MALICIOUS

PDF

84.2 KB Created: 2021-09-22 16:49:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 81c972205ddfe5a39c467db2453290a5 SHA-1: e1dc5b056564aa1d8be2da8fc445268d79069f18 SHA-256: 8955f164ec223885cf43e983ba37fc614582f8d5606cbd7cd9be111022953c65
216 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple PDF files hosted on compromised websites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of MFA lure heuristics further supports a credential harvesting scenario.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://vico-real-estate.com/ckfinder/userfiles/files/sixudozotiva.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/thrvnp2hab5i95tidpi2b5gp1g/94053532697.pdf
    • http://coytex.net/ckfinder/userfiles/files/87114883821.pdf
    • http://jycjqj.com/uploadfile/file///2021090407173457.pdf
    • http://pronobile.de/catalog/file/3536853825.pdf
    • http://orem.mn/uploads/files/69364856012.pdf
    • http://levne-pohary.cz/UserFiles/File/45406194256.pdf
    • https://akgoz.zemta.com/uploads/files/12046634567.pdf
    • https://inprovitpuertorico.com/ckfinder/userfiles/files/niwerajokejozanifesatutoz.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16147c9487a3d8---bulagaradawirevab.pdf
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/61538621054.pdf
    • https://sofahatinh.com/upload/files/25689889774.pdf
    • https://dailyiat.com/html_upload/file/85201826860.pdf
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/3815763659.pdf
    • https://pgprojekt.pl/Upload/file/22148294614.pdf
    • https://netron.pt/app/webroot/media/files/zeposujopeweguj.pdf
    • https://oilbasaro.com/web/images/ckfinder/files/20210915104755.pdf
    • https://grupa-energia.pl/attachments/file/99407753439.pdf
    • http://fapannimario.it/userfiles/files/65119283191.pdf
    • http://textstricker.de/benutzerdateien/wesakaxura.pdf
    • https://bizimpin.com/calisma2/files/uploads/baparubemewelefunipuz.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613f211bda9f6---69249484438.pdf
    • https://pchome.uzai.ca/upload/files/18212002530.pdf
    • http://zvaracskaskola.eu/editor_uploads/system/files/45624963537.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=unsynced+contact+android
    • 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_off0000e5b5.bin
46036d49670cd323fff67c94fab9787499f93222ecc8311c10b352c72fdc6ea0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B5 10440 bytes
font_01_sfnt_off0000fd8a.bin
1d2928c1482651f87fe248a63ed51078629e38728ad8e9764813cdff5a23dbfb
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8A 17720 bytes
font_02_sfnt_off00012b46.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B46 16792 bytes