Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0c734fd9715da67…

MALICIOUS

PDF

87.7 KB Created: 2021-08-10 08:08:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d7f325788acf5bebb32303ece294df7 SHA-1: d230212ab798d732e82e6cfad07918fb9d9a7546 SHA-256: b0c734fd9715da6776aac9db020005aafb3bb7d9edddb8f7b4421394f257653f
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm and a callback phishing lure, prompting users to call a number under the guise of a billing or security issue. While no scripts were extracted, the embedded URLs and the nature of the heuristics strongly suggest the document is designed to facilitate social engineering attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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.
  • 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://queure.ru/uplcv?utm_term=directv+wireless+video+bridge+connection+diagram
    • http://rana-international.com/userfiles/files/74045392042.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef77fb572f---pulokumikelezonaderida.pdf
    • http://airconbank.com/upload/fckeditor/file/18450318283.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e5600544522---80511844224.pdf
    • https://kurishupally.org/userfiles/file/tepikuvolurorikesan.pdf
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/82e570a2b7fd9c284d1798498e6bd26f/392657445.pdf
    • http://teormech.ru/teormech/usrimg/file/rerakexufesubule.pdf
    • http://carriewoodfamily.com/clients/5/5b/5b9f2fb360c4065436fb7fe1267c3612/File/16946191332.pdf
    • http://gesundimjob.at/images/content/files/5601683426.pdf
    • https://ferest.ro/imagini_ws/56684553979.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/mg93n5nap63jbhs17oo6e73554/38987472042.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b45e0b66442---60948189864.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d6ff829f6---97949034295.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160d1d33d48da6---fizig.pdf
    • http://bscsaoner.in/ckfinder/userfiles/files/96894824712.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16094d4d8ea4e7---54507454325.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/410477bbbb9db4317bdadae5c30de516/vusokovonasumadimin.pdf
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b56c6ba89ba---96201191069.pdf
    • http://lauraestetica.com/userfiles/files/82866040997.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/ddf689683be95a795636962cab1bcfc0/44717431241.pdf
    • http://tamker.hu/userfiles/file/64658133459.pdf
    • http://grafiport.com/userfiles/file/sixurexiwi.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606d342067871---25288817936.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_off0000ed9a.bin
935254f99dc5980dec64aa89ddef1bc3c3b7a2849663ec5d668bb8d48ca86927
pdf-font-stream PDF embedded font (sfnt) at offset 0xED9A 11004 bytes
font_01_sfnt_off000106ff.bin
bc7f2aa20fe95df1230f22c0022d4de135f4142f79962f60fc2b183c1d788614
pdf-font-stream PDF embedded font (sfnt) at offset 0x106FF 18424 bytes
font_02_sfnt_off0001376d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1376D 16792 bytes