Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8432c9b607ec507…

MALICIOUS

PDF

74.6 KB Created: 2021-09-18 18:54:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 60eaf7cde6681360f42da09612745458 SHA-1: a14177388ebb57e5ee345d892e0f7e2c4bf92ea6 SHA-256: a8432c9b607ec507f4518810b5651212d990fc6457e8139a98b545fb4aa765c6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically related to phishing and hosting links on compromised sites. The presence of numerous URLs pointing to PDF files on various domains, including compromised WordPress uploads, suggests a link farm designed to distribute further malicious content or conduct phishing. No scripts were extracted, but the overall structure and URL patterns are indicative of a malicious distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://drafthe.ru/uplcv?utm_term=how+to+hide+apk PDF link annotation
    • https://samuelben-horin.com/userfiles/file/polakepaluzafudaw.pdfIn PDF document text
    • http://tindangnhadat.vn/upload/files/gutamovutu.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/72811274238.pdfIn PDF document text
    • https://network-italia.it/file/94433283612.pdfIn PDF document text
    • http://hk-sai.com/ckfinder/userfiles/files/wukipadomokelaxuvogigebu.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/39377059533.pdfIn PDF document text
    • http://miydz.com/mingyi/images/userfiles/file/37154765380.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/lizivosavanud.pdfIn PDF document text
    • http://gdwtechnology.com/fckeditor/file/valiferabodukeriwasapata.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/50054649353.pdfIn PDF document text
    • https://pellevah.com/upload/files/84396059618.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161393ea9e3b75---bopafasujokuwulutagesixe.pdfIn PDF document text
    • http://thewellmanteam.com/userfiles/files/xapawapifaworomijemow.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b58b4445d5---gobokolajuvaviwex.pdfIn PDF document text
    • http://balone.net/_upload/file///20048454709.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/49697038709.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/82654949105.pdfIn PDF document text
    • http://norrlandet.se/userfiles/file/jusokurosebunavidike.pdfIn PDF document text
    • http://lavalnerina.com/userfiles/file/vativovi.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/s1ka6afq0bgqspqcm7cb8ljrd5/25334636220.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/musinubuweb.pdfIn PDF document text
    • http://keemunblacktea.cn/uploads/file/09052651258.pdfIn PDF document text
    • http://globalsublimation.net/uploadfile/files/fekineteze.pdfIn PDF document text
    • http://rubella2.integra-sh.com/userfiles/file/41335192432.pdfIn PDF document text
    • http://jiehuist.com/userfiles/files/10753266209.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_off0000c240.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC240 17340 bytes
SHA-256: 9e562bdfa62c79a6034edda49c6fd77b4dbfabba383c7bfeff8f16e8389f358d
font_01_sfnt_off0000ee32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10649 10240 bytes
SHA-256: 5b7aeb6782dd305ebb46f8133fb2bfc740550dbfe9b340687c4ce6bec118ebc6