Malicious PDF — malware analysis report

Static analysis result for SHA-256 21e55b48a24754df…

MALICIOUS

PDF

79.9 KB Created: 2021-09-02 10:38:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b9a4bf8dac3cbf8d29485408364b0d69 SHA-1: f430c56b5d71444952b22111ebcc769bda4de575 SHA-256: 21e55b48a24754df0bedaa10f7eba81324bc0905df83f0d03da9ca85597da875
176 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, with heuristics indicating a malformed exploit stream and a link farm pointing to compromised CMS uploads. The numerous embedded URLs, many hosted on potentially disposable domains or compromised WordPress sites, suggest a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself is weaponized to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7d8e0b779---18002693209.pdf In PDF document text
    • https://worldmedglobal.com/userfiles/files/lijebudu.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f2675470bf---87552510197.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a79628fd3c---pafimitimarebe.pdfIn PDF document text
    • http://studiodispirito.it/userfiles/file/nosokalajir.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/6id0d2i72002cuea2o52nmp3q9/nefogozegegudegafizowufuf.pdfIn PDF document text
    • http://freewest.at/nipojoveratetifes.pdfIn PDF document text
    • https://johanbjerke.se/userfiles/file/voxenevenemitado.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/87606164482.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/piwajed.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecf09aa257---67748913704.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a75686dd556---87123063005.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/5bd4ba2840f9c55764944be39b0c5a82/16047563814.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/u0pcpbn99tp84ddhvtu8k8shp2/rojogo.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/2714637369.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/dac869c4cb01362c736b09d349280aa5/81019668267.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16072892de4752---44746025868.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b388bece3a9---65651443699.pdfIn PDF document text
    • https://sproname.com/files/userfiles/files/90534334485.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/nogesozuvopesufamude.pdfIn PDF document text
    • https://kompaspt2.com/contents//files/sozekavelowiwuxaxizubetom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=definition+of+homeostasis+in+anatomyPDF 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_off0000d742.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD742 10448 bytes
SHA-256: e7a72802765c1ca53b0e1d8d1b10f8ef104b23327bcb3129fdc0689d859dca21
font_01_sfnt_off0000eed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED9 16808 bytes
SHA-256: fa2e6e3bb5ba2e4af39bfea1c8fe7efdd7cfadff0bfc8ff9183815d8f6f6238b
font_02_sfnt_off00011a53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.