Malicious PDF — malware analysis report

Static analysis result for SHA-256 1815f27394139fb8…

MALICIOUS

PDF

80.9 KB Created: 2021-09-06 11:18:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8e3e7dbf107bbf5f0d7562153f972710 SHA-1: 824cb94e2eb3834808cec9d238b8888793e1dc42 SHA-256: 1815f27394139fb8cb95bf07a2e4317ef89f25f77e0c7df8f6e77dd10da5d615
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs hosted on potentially compromised or disposable domains. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests the document's purpose is to distribute malicious links, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://pistant.ru/uplcv?utm_term=suspension+system+parts+and+function+pdf PDF link annotation
    • http://delve-cr.com/uploads/delaj.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/65493233517.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac27fa114a---75374371325.pdfIn PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/figevavoxe.pdfIn PDF document text
    • https://pesonabali.dswip.com/ci/userfiles/files/rapogimubixin.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a3729d7c8ef---bifinox.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/8533230559.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/82527440860.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/3385695029.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071eaa7d14ce---tatejoxez.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/wewukemudotisijivewawor.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/6pk5u6qelafngef8kl69f8a5hi/vetidus.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a33925ec391---zodubenikig.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/bupesipatagela.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/33614e25359c282a52028918838f9247/13246318847.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/7c08167fa9263b059d85e5cb979d8668/pogeritilegonadolisaveku.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/3bee2c0999af88b167fd1bb7542b4942/wamulaxifegif.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/901750eb05dd8afe493f47e485c84434/29186803674.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c90e3313d4---6390510321.pdfIn PDF document text
    • http://secretlove.ch/ckfinder/userfiles/files/56191718157.pdfIn PDF document text
    • https://nenanhduong.vn/Upload/files/ziritopur.pdfIn PDF document text
    • http://cbafjvn.com/uploads/userfiles/file/28879772310.pdfIn PDF document text
    • 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_off0000d92d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD92D 11024 bytes
SHA-256: 824a402745a1b365f825093153a5a05fb13337d75e59902432be2cfd6637c204
font_01_sfnt_off0000f2d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D5 16596 bytes
SHA-256: e048322e06ef167eece19c0788fcf5772ed040c085c2f42053eb3cc41dd6646b
font_02_sfnt_off00011d88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1