Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c6f3324a82a9bc6…

MALICIOUS

PDF

88.2 KB Created: 2021-06-09 07:20:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 2d00b1a98a4d3b7094698292bf81a0df SHA-1: ae50c9696356550c6a2ebc22a59f0f772f81e3b8 SHA-256: 7c6f3324a82a9bc64927ef15cba796457be1f673c15b55171574dafb35b4a0e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The document body is heavily obfuscated and appears to be a lure related to 'dividing fractions answer key'. No scripts were extracted, but the overall structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://huntic.ru/uplcv?utm_term=dividing+fractions+answer+key PDF link annotation
    • http://nw-line.ru/generic/uploaded/80959016629.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/kc473suir5v4j8svqnp4j9a1u6/96699108324.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/33412115440.pdfIn PDF document text
    • http://etnorom.hu/pictures/63097820891.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/90183122985.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/vabefupagozorose.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7aa8d126be---3300719867.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/f92d9e484d3b72cf671dd4aca7d70182/tukabide.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/89066282945.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a315d03be98---85598720348.pdfIn PDF document text
    • http://porpora.biz/imagenes/imagenes_contenidos/%5C/daxofekevorunerikozuvoma.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083842b82bc8.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/75157280f721db6513c9e77cd75c5b71/webubumofapupurud.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a3fcc3aa7---95279174991.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/bpnocus0c3j4114n9eo0oohfdk/83568329613.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ba193a15ede---30916403262.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • 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_off0000fb89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB89 5472 bytes
SHA-256: b2dcff68c8025aa5acb2a685a17d5c5a84b75699e461ab8bb6915bfb7475e949
font_01_sfnt_off00010e62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E62 13416 bytes
SHA-256: d9c2f900514e6c0ca77532984ee7805ee66d8efd71b5a03337c13940a3d7d6c6
font_02_sfnt_off00013975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13975 18492 bytes
SHA-256: 5f837538cb1d18fb444361e8289f0010f9ea82b3355a168dc8a300679e00edb5