Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9f73cda5cd777c5…

MALICIOUS

PDF

89.2 KB Created: 2021-06-29 11:14:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: cf5542f74b4f9e61e70cb44ad15f8007 SHA-1: f4088ce546aaf99784caf6e8cede5018bdbd66e0 SHA-256: c9f73cda5cd777c594afff95be5a5634868b487cb4ee4943adf71a1f23635eb4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised WordPress sites, indicating it functions as a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://jshtextile.com/UserFiles/file///jedulisub.pdf In PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/535v1bll0c5kl9f200k1tgedbb/wagikegukebef.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/2021619211412624.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/20fde73bda9308b338f71725d41115e3/92610084180.pdfIn PDF document text
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/bnfjjmt3ciqiltvk51vtb1c2du/94783596334.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/lmdf2vl3ds3ihg6mame8bs96n2/lufafinirarutudale.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/e3214d3567aeb728c804192668059e3e/5103563933.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d7be4b7eab6---fovutagilejisol.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/4c9e9519922273018ef997bc71bc95e7/25609084174.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/432560b20433684daff86d08c8472fb6/raladagozos.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/4546ca7122e5a66bcafdaaad0b3650f0/94325025825.pdfIn PDF document text
    • http://myexamadvisor.com/fck_uploads/files/vesobezuripaduwemotujaf.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/47481879090.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160da16310acd1---68242943999.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/e57efa3106ac6ec1cbf3772e805c9bca/kuxozesopaduwaxenekareked.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/736o8o1k8jt17rtkr2ceggmvcc/vuded.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/88b770cdf3bf58fbe31316ef783a90f2/8746255259.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/c9d897a2cc11331fea6e88c7eaf042bd/51842207970.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/befuluwidisubuwuwafujofu.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/o2n18rba2o19s0mcm3ptvfjai9/gifaxikipolenegegojej.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d3abfc80102---6654569501.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/t3msrjimuaffft9ak894lc6jv0/podigawawa.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2303290dd---25113161588.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=erythematous+papules+on+legsPDF 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_off0000fa92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA92 10804 bytes
SHA-256: 334166348dcd237481b58b7d7fe4a25276963edf05cd89f73e0c4e113785941f
font_01_sfnt_off0001135b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1135B 16988 bytes
SHA-256: 432395476e44961bf7a721c380c9e16b48d731810b60ac12e4ec22ef65d5711a
font_02_sfnt_off00013f83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1