Malicious PDF — malware analysis report

Static analysis result for SHA-256 427431cc87976132…

MALICIOUS

PDF

91.8 KB Created: 2021-06-25 22:00:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: a45eb222eb2b0e094d282091601249d0 SHA-1: 444a9c564467922b6728b6066e43486bf151c875 SHA-256: 427431cc879761323f39754a9775dca77a509fa7f89b1eeca1dee86e5df67082
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms. ClamAV detection and ML classification strongly suggest malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160991816c31e3---48599842009.pdf In PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/1h2i5qoekh7q6d6rklvmevfula/34236571628.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/43154a203a6b520602a45021024a4538/siluneked.pdfIn PDF document text
    • http://dagmar-e.de/userfiles/file/tigolulupagofoturowop.pdfIn PDF document text
    • http://bruisedreedfoundation.org/clients/4/4d/4d9d7eec3bf3a09fa0457ace138f6a4e/File/15832512249.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/9311381902.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4d279e30a---rojuka.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f083a7beed---vumelegulatom.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f8f4ed9644---75095592308.pdfIn PDF document text
    • http://master-sign.ru/ckfinder/userfiles/files/luvatotapirineguzegig.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/3c6ab7c5d0daf4fe1f885d4d5147fa56/59966810308.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/de7661441e9a7c5d2e8ad1130241e4ad/wexebibalodelu.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b78d1a53024---bakojepad.pdfIn PDF document text
    • http://maxidmum.com/images/upload/fck/file/mifewiwabagobi.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/vasaxisugukupoxexewizez.pdfIn PDF document text
    • https://woodfur.in/userfiles/file/31086214625.pdfIn PDF document text
    • http://greece-ex.com/images/blog//file/47741777215.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16090a44542cfe---tixifulepovamekaxenepinat.pdfIn PDF document text
    • https://ckmandarin.com/uploads/24839548444.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c3ff1ad6c---15144688755.pdfIn PDF document text
    • https://castel.ro/userfiles/file/49180174706.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4ba60a6ca---tawazoxalaj.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/b918154d82b8e2390777178524d59376/ginodegawegerowo.pdfIn PDF document text
    • http://whatifitspossible.com/ckfinder/userfiles/files/76610287445.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/5819675ebfc3b757a8cb42f923a049b7/10225466371.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=the+fault+in+our+stars+free+online+bookPDF 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_off000104b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B7 10604 bytes
SHA-256: 77364cf93befe7b992f95783c1e35b4586f92fdc377ad03115686e2a996716d9
font_01_sfnt_off00011ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000134fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134FA 17116 bytes
SHA-256: 6fbd394189b3395508ecd2eb4643b58c7b3166375287feb3c848b57411048fb6