Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a50527dd325ee7…

MALICIOUS

PDF

77.4 KB Created: 2021-05-06 01:23:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 260732ebd1d4487a85f64eb4dd8487aa SHA-1: 407f5e743988d13a8fecde3c727a01cc49c81411 SHA-256: 50a50527dd325ee730216842cfe9abd54d3b80741baa3d418a60592b7dc2264f
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the heuristic firings and URL patterns are highly indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • 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://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/h76cgta863pd75ccfkr89t49mg/kivikavokexu.pdf In PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e739e10eb1---34107315017.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/55882778715.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6d6d1e898---xijavogofube.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160864bffc7802---74777407944.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/5f19f9e4892d595e3a1d3c0d5ee4497a/dukewazidu.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608ca215442f4---46534422510.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/h0iohcjlj8s9cvuorfiv7uias2/zojizopenemilodin.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/2d13eab045e66d230774b76d54ffca3b/64405438223.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/jusivotosusamokutog.pdfIn PDF document text
    • https://krippner-schroth.de/wp-content/plugins/formcraft/file-upload/server/content/files/160753fb4ca619---kigipuperisumi.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160768d97949ef---kusamiwoxegijedogiz.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8a5213ee7---judoxofufudo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=centralismo+concepto+pdfPDF link annotation
    • 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e4e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4E9 5112 bytes
SHA-256: 598d665e39a608b5fdecd2671ee762414c2bb7a30809ab80e087f11eed5c444f
font_01_sfnt_off0000f62b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62B 10728 bytes
SHA-256: 1be44b77796950de10326eba8676417415598c59095087a7d8221507305d739a
font_02_sfnt_off00011928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11928 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c