Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f36f28a6ae70b48…

MALICIOUS

PDF

75.3 KB Created: 2021-09-21 00:04:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 97c101447aaa92b30d357743d179952c SHA-1: 94f7b568d4f74c813477a2c2ad4ad29765d6dbda SHA-256: 0f36f28a6ae70b48ef62074b58b287600a2a4c2218af1a1270766dc493f59271
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to various websites, some of which are hosted on compromised WordPress installations. The presence of embedded URLs and the nature of the heuristics suggest the primary goal is to redirect users to malicious or phishing sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://queure.ru/uplcv?utm_term=kozier+and+erb%27s+fundamentals+of+nursing+pdf
    • http://hoachathoanggia.com/userfiles/file/4975565412.pdf
    • https://mycocoa.org/images/upload/files/30372764693.pdf
    • http://theprofitnesstrainers.com/userfiles/file/sonoxajozumi.pdf
    • http://rydelko.pl/userfiles/file/62925267422.pdf
    • https://nuttydog.hu/ckfinder/userfiles/files/wiravawo.pdf
    • http://turinhotelcompany.com/userfiles/files/309290924.pdf
    • https://sdhouse.info/ckfinder/userfiles/files/67145968919.pdf
    • http://studiomuraca.eu/userfiles/files/95150994960.pdf
    • http://boxethai38.com/upload/file/23903054160.pdf
    • http://poiskvod.ru/images/file/97514843785.pdf
    • http://beautifulmoda.com/userfiles/files/48083984582.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612faa4b3a43a---naretituwizulezus.pdf
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/32775902287.pdf
    • http://xn----1-6cdapb2bdyqawnpcindqfc.xn--p1ai/media/file/14152333539.pdf
    • http://triple-a.co.th/ckfinder/userfiles/files/21510835094.pdf
    • https://aradmissions.com/ci/userfiles/files/87637311962.pdf
    • http://lab4050.com/upload/editor/file/96486023458.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/710bfed43b4a3e6a6e902f847841bba0/jafewerifilabek.pdf
    • http://khodahoanglang.com/admin/webroot/upload/image/files/326481761.pdf
    • https://aglogistics-bo.net/userfiles/file/napevudo.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/djspn9o0o6t2eld8o2kqpp87j0/xafetozojopawufad.pdf
    • http://biplano.eu/userfiles/files/monejarageronarojoj.pdf
    • http://thaoduocvn.com/userfiles/image/file/29589273566.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000be66.bin
bbff3ef67176e213b57ce6870d5d7442c013fc906536c400458d4d5158b8f09e
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE66 18424 bytes
font_01_sfnt_off0000edd5.bin
68aa8425d4ca02b6f3af0ad40d924902fcff16f127f4016af4d19a41a45b1abd
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD5 11164 bytes
font_02_sfnt_off0001078d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1078D 16792 bytes