Malicious PDF — malware analysis report

Static analysis result for SHA-256 3929bb3567c61d28…

MALICIOUS

PDF

87.5 KB Created: 2021-07-19 02:21:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 89fc92b561a5bb0d71eb35bbc5ad7347 SHA-1: 1d8c2901a163a98404a0abe138ff3cdb88d4c9b8 SHA-256: 3929bb3567c61d28fc32d8829140f7a155c724a293cd8f483e9cd286ebdaadf3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to compromised WordPress uploads and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links. No scripts were extracted, so the primary attack vector appears to be the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a48b58e9792---23027387172.pdf In PDF document text
    • https://codecs.ro/images/file/12580818022.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/9569678591.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/10564777237.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae710fdff9f---piwajajarapezin.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e95154da99---45663924788.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/81ca8303972826fd54dc3e59f9b23629/90463895884.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/kedigulitikasovizakomo.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/ditivetitigabidunexe.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/d7noks4mavgpc42oj4n6mgv601/pujowasonexonutiperij.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///24908470742.pdfIn PDF document text
    • https://hotellemaritime.com/hotel/upload/files/kujisezerifa.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/81514724723.pdfIn PDF document text
    • https://majubesar.org/contents//files/76177829834.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160946406de34c---zukefomon.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/4b3ea9b538c95f2fd4e6addf1306294b/2949573917.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/zerotusemikirulajapudigex.pdfIn PDF document text
    • https://bamor.org/userfiles/file/47733309734.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e19740b1690---30830925038.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160ce9198d8a50---xolevabogid.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1147534ea7---69876563761.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/81758754687.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160862c5a26cad---29093300517.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1607262a4de44c---sogoposumunuto.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/c8d154dde7bf013ea1fbc3baf27b2959/47784231071.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=sample+business+plan+for+computer+training+center+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_off0000f266.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF266 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A7D 11280 bytes
SHA-256: 4b6646a70bb3ac74a0b524bf903564442ea05648aea63be4fe7cd54c940a438c
font_02_sfnt_off00012479.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12479 16960 bytes
SHA-256: 0c1db3fe6be0efd10363b0400e5faa1dc3479ce2b76efa564bc9bdd6f63a5923