Malicious PDF — malware analysis report

Static analysis result for SHA-256 a81900cf96b85d9c…

MALICIOUS

PDF

68.9 KB Created: 2021-09-12 20:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6cd9a9ecd7bf92ded9cea3624546eef0 SHA-1: 54c88950997fa94933e948d52bd8eeb4247a3f24 SHA-256: a81900cf96b85d9c2009d6c407f83c52115473e2894cae44abc12a37247704e6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://titibbs.xyz/js/ckfinder/userfiles/files/sunufomiselobobabuzudu.pdf In PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/8b539df1ae827f94ade2a31d411cae78/11129430440.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/guneka.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613162e598b8b---sokulofutevilijosisogefu.pdfIn PDF document text
    • https://www.corpeverest.com/ckfinder/userfiles/files/69829622210.pdfIn PDF document text
    • https://amgaa.org/temp/files/suvowusuxozokezazobaxijuf.pdfIn PDF document text
    • https://dukupahit.com/contents/files/82795209969.pdfIn PDF document text
    • https://fasaac.org/temp/files/tixekunerotoseziboma.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/zotim.pdfIn PDF document text
    • https://www.potravinyav21.cz/ckfinder/userfiles/files/vasuxixedomawokumabaled.pdfIn PDF document text
    • https://zzhqhi.com/d/files/98565134913.pdfIn PDF document text
    • http://savitapiti.org/ckfinder/userfiles/files/xukatumagunugaf.pdfIn PDF document text
    • http://vning.net/filespath/files/20210906204930.pdfIn PDF document text
    • https://kfk-dekoration.dk/images/uploadedimages/file/pagubirase.pdfIn PDF document text
    • http://nriloan.jctoursandtravels.in/files/pabil.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/xexibosubiruravotuta.pdfIn PDF document text
    • http://gardensyellowcab.com/admin/images/file/17891763564.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/885ee3f295cf5159352ba65e52330986/43895608579.pdfIn PDF document text
    • http://simsvizag.com/admin/uploadedfiles/file///75164911108.pdfIn PDF document text
    • http://kozhencherrymtc.org/userfiles/file/mimisopeximufinarorux.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109130027301241.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/71696541730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=imaios+e+anatomy+apk+crackedPDF 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_off0000b159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB159 10784 bytes
SHA-256: 3d043f24f6e1f2483ff1e29b006e9ca08256fbe37595ab244e0cf81233f5f4dc
font_01_sfnt_off0000ca3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e24e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE24E 14352 bytes
SHA-256: d5883375bcb7c6d3fa21332d5ff0dc5402ba97d281850230d1503523406dea0c