Malicious PDF — malware analysis report

Static analysis result for SHA-256 b52c7a357ea5935f…

MALICIOUS

PDF

76.9 KB Created: 2021-09-27 00:09:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 56027503d3f1241fe813bb6bf7c71f1b SHA-1: a320c38900d657a0ca81cc0981e8d645902baa66 SHA-256: b52c7a357ea5935fbf0b8e0962fc8244263309f899652a022b6da03a68656527
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farms indicates an attempt to deliver a secondary payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://wastran.ru/uplcv?utm_term=spy+on+private+instagram PDF link annotation
    • http://autodilygood.cz/files/file/tikokilatufawuwob.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/doterirom.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/e4230e2dc663e0a55735ff98bd5fb1e5/24155843254.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/kefuzukolivodozibejosude.pdfIn PDF document text
    • https://www.potravinyav21.cz/ckfinder/userfiles/files/zikozovexa.pdfIn PDF document text
    • https://novsport.com/content/File/48999542784.pdfIn PDF document text
    • https://giritrademark.com/content_files/files/sewer.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/90591427532.pdfIn PDF document text
    • http://infoegrafica.com/userfiles/files/maritikesidaziwa.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/82665517321.pdfIn PDF document text
    • http://craft-personal.de/userfiles/file/39523829169.pdfIn PDF document text
    • https://quangcaowebsitecomvn.xemlaco.com/uploads/files/jafotatikivedidanip.pdfIn PDF document text
    • https://gangwontaxi.com/FileData/ckfinder/files/20210917_A7DF313D085F50A5.pdfIn PDF document text
    • http://hydrogears.com/survey/userfiles/files/9124620888.pdfIn PDF document text
    • http://ombs.ru/uploads/files/mixanagatofepuna.pdfIn PDF document text
    • http://hicoweld.com/shop/fck_file/file/22054394120.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/busekiretupudejefedavuvu.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/855a3b9bd1389a2b5f975ea69323bcae/19675967896.pdfIn PDF document text
    • http://okzawidow.pl/img/upload/files/28348462183.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/17562733043.pdfIn PDF document text
    • http://thetsaban3watnuea.com/UserFiles/file/79761838169.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c997260e8---lobugokufavi.pdfIn PDF document text
    • http://chiron-ventures.com/chiron/home/img/upload/files/210912094954340438gwoc3.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/sibaz.pdfIn PDF document text
    • http://charmingcurls.se/upload/file/84265480746.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_off0000c346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC346 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB5D 10804 bytes
SHA-256: daeb9e82b00515b6eb00fe43d09a93771d5666eebb05fcc66be4497dcd93b96b
font_02_sfnt_off0000f450.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF450 19116 bytes
SHA-256: 286cde320d99cc01be23af67c4323cd7c86f20530e88b313efe31237b6d59e18