Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fd751082285d0fa…

MALICIOUS

PDF

82.1 KB Created: 2021-08-31 02:36:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fb6041a6b18c5353b9580ac4eb360d8d SHA-1: 1926c6825ac5a39fb3064b5c5ae119de3f021646 SHA-256: 8fd751082285d0fa7d7ae9642dd663ed9f9c6bb62ba8d0cecddbd3d36331d990
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and ML classifiers, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The presence of numerous external URIs, many pointing to compromised CMS upload directories, suggests a link farm designed to obscure the final destination and potentially host phishing content or malware. The primary attack vector is likely spearphishing attachment, with the PDF serving as the initial lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://krisoc.ru/uplcv?utm_term=example+of+self+introduction+in+college PDF link annotation
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160864c4e72198---fexirodojileza.pdfIn PDF document text
    • http://masterref.ru/editorfiles/file/fibatajug.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160a52ace93007---lifuxu.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607d13fc07137---67478039856.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/varitogi.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/kigisipugapasu.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd871b5cb6---91397440693.pdfIn PDF document text
    • http://lesmashclub.com/imgUpload/files/52937052636.pdfIn PDF document text
    • https://alharithiforcameras.com/ckfinder/userfiles/files/zalevile.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/0i2f2p7dv9381cr0hg09atce27/bogeto.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/3107cc7447d43e3e8f0bd1ba88ca58e2/6779039933.pdfIn PDF document text
    • http://secretlove.ch/ckfinder/userfiles/files/57499884885.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/18475045206.pdfIn PDF document text
    • https://mmoxx.mn/userfiles/files/83810791363.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160d99432d6cc7---59255343839.pdfIn PDF document text
    • http://messtores.ca/fck_user_files/file/71139990583.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/b5faf697bd1ea4b257242e206b8d351f/67896613471.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/somaboxetu.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16079001e3bbb3---kalubokiris.pdfIn PDF document text
    • http://www.diplomat2014.ru/ckfinder/userfiles/files/witedebunuwesu.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608afeea7261a---14094894276.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/4856196c00ed40378d8a3199c3570b04/wumepozizog.pdfIn PDF document text
    • http://www.tekkoo.net/images/library/File/20809245891.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_off0000da5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA5D 17352 bytes
SHA-256: 869b6ddd66e259cc882ff7e3126a3b4a9e7501eae7a93c173dabe22d0b253ed3
font_01_sfnt_off000106fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106FD 11148 bytes
SHA-256: 204a32d44dc3eda3ae0d6ff5a12c98fa58517cf885d0a127650388ab66eb83a1
font_02_sfnt_off000120d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.