Malicious PDF — malware analysis report

Static analysis result for SHA-256 f51f274cce1c94bd…

MALICIOUS

PDF

91.1 KB Created: 2021-06-28 06:34:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c77274ac0a4f37e2eb26acfab4b48cbb SHA-1: 26277477f7e0308f135688eb730f6b831418c7a6 SHA-256: f51f274cce1c94bd0e3276a3e7105e156365472ea257ab98d8822101957c9719
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate it contains a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to distribute malicious content. Although no scripts were extracted, the presence of numerous embedded URLs and the 'invoice/payment lure' heuristic strongly suggest the document's purpose is to trick the user into clicking a link to a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://alihuata.com/userfiles/file/81641863773.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e80e89b38---1656501379.pdf
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/56de84afbee26f74d96cdca4ab2caf57/23194525178.pdf
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/519701ca5a0b8692539419e02775aeb6/40445140242.pdf
    • http://maychamsocda.vn/images/userfiles/file/rolep.pdf
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/vflkvpmht94jfabc1qb6vkru2g/61830518029.pdf
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/c319e52baeaf3b7b0711bdc59d729917/vovuworozapovuxum.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160792d1baefd7---54892093352.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160773a9d74755---basimefogasopa.pdf
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/f1685ba0a3c4374738492ba126db1a62/fekezuzofitode.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160beeb7317660---88499458591.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/f1d2b78a96c4419a0d185461631cea04/kuzimukagaresom.pdf
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/ef2b56f7aff4a63ef4bb8f977234795a/36591609491.pdf
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/5teq9on5g0gnjuf47trpfpa9e7/gewijefumikuloruwiroze.pdf
    • http://digemnd.com/UserFiles/file/48967655675.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b955f36d423---52409884055.pdf
    • https://ewastexperts.com/userfiles/files/16327669169.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/u13r9rkthghsm787t652hqppcf/44382848106.pdf
    • http://ahkkpcm.org/userfiles/24142711989.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607700723c7f7---60581429543.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/2251372f4813695f5fdadbd8893093ea/lexodiniduvikivanedax.pdf
    • https://najlepsze-w-polsce.pl/uploads/texumadopomuz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=land+contract+terms+michigan
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/acb2a99338c3e141221c5dab8f06636b/91812411590.pdf
    • 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_off00010179.bin
0f7bce91979bdd51b61e9a1ee9786ca78f6cab09e84c0d28f5d6ede598431093
pdf-font-stream PDF embedded font (sfnt) at offset 0x10179 17572 bytes
font_01_sfnt_off00012eda.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EDA 16792 bytes
font_02_sfnt_off000146f1.bin
f8643b6330a65115ceec59358413b4c730d3816c97556684c77f3f00b82bcc7d
pdf-font-stream PDF embedded font (sfnt) at offset 0x146F1 10728 bytes