Malicious PDF — malware analysis report

Static analysis result for SHA-256 21e52f53901abaa4…

MALICIOUS

PDF

75.1 KB Created: 2021-09-05 08:36:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a4779894353c876ef5d7dafe896cd59b SHA-1: a1d17192caf4a066fdaca2e0a956379c01b77d1e SHA-256: 21e52f53901abaa435c5dab59258aa70978fa28373300b478ebdbb476614bfcf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, indicating a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://doverhighschoolhalloffame.com/clients/2/2d/2d76883e1086210ef8e2c43836b0327f/File/vutisetibujebuwe.pdf In PDF document text
    • https://allianztc.ro/files/file/32895547396.pdfIn PDF document text
    • https://beldaoyun.com/calisma2/files/uploads/sepigifakafafiju.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/379522abe303a54ae1b96d29a0f67c20/61483283936.pdfIn PDF document text
    • http://gloria-eurex.com/93359055491.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a6e695b5a---89012476215.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/o7sv5mkvucd5h14ef40v1m967v/50605753879.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/sepidi.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b1483e86135---losobinerakimovenoma.pdfIn PDF document text
    • https://hchoanglong.vn/userfiles/file/dufulejeremifemabad.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acb36817fd6---wuvafubokevenisusoteg.pdfIn PDF document text
    • https://chennothinterios.com/uploads/file/nekebotikivurijizexakasik.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fc51153e1---45519218804.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/76494177425.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/82923525312.pdfIn PDF document text
    • http://rauvuonsach.net/images/uploads/files/xogigesawukofuj.pdfIn PDF document text
    • http://greenhousehotel.vn/uploads/image/files/21907439320.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/53414978639.pdfIn PDF document text
    • http://flemisterbauldingfamily.com/clients/8/82/82a21d9598fc66f9117a8fb7222c8fd0/File/xatapezepamimademes.pdfIn PDF document text
    • http://findmecakes.com/userfiles/files/85405331678.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/pugitisurivovaluva.pdfIn PDF document text
    • https://vettercycles.ch/userfiles/files/nawejewosirixemo.pdfIn PDF document text
    • http://khautrangkhangviet.com/upload/img/files/fawonadazut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=fissile+and+fertile+materials+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://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_off0000c0de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0DE 17812 bytes
SHA-256: 7d344448bedd933f7323d6f3223961d5cc6a77ef943627bc1a50f43f681e13b4
font_01_sfnt_off0000ee9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9E 10516 bytes
SHA-256: 240c53a92c14a286144612e16137e4758bfda6ae6dece4a12b7775eaafa4358e
font_02_sfnt_off0001067a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1067A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1