Malicious PDF — malware analysis report

Static analysis result for SHA-256 9524a9d114e4bca5…

MALICIOUS

PDF

93.0 KB Created: 2021-09-13 16:29:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 92898d6a7e6585a68b75e08fb35e8fe1 SHA-1: 671d75d88b0a014ef0ad05a58dd345706f3f87cc SHA-256: 9524a9d114e4bca59729f76f9d53dae7b9543e0c88fb420fcc7b8c20cf87af1d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm PDF. It contains numerous embedded URLs pointing to various domains, suggesting an attempt to redirect users to potentially malicious websites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links, commonly seen in phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ketchas.ru/uplcv?utm_term=indicadores+de+calidad+en+enfermeria+pdf PDF link annotation
    • http://usaoxin.com/userfiles/2021-9/file/deludenurudufemojetomivox.pdfIn PDF document text
    • http://www.huescalamagiaenfotos.com/userfiles/files/sozuvavegokoxaregizepewo.pdfIn PDF document text
    • https://krusomying.com/data/file/789754462.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613be04de8c69---teterinagifegido.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/ieub02joki16n389g0bodm8jf9/36808267813.pdfIn PDF document text
    • http://geologocarmignani.com/userfiles/files/kopesifikumotisem.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/rifixopolozowabogevo.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/jativulutomufuboguwiguleg.pdfIn PDF document text
    • https://ifbscalidad.eus/files/galeria/files/vovosowokakom.pdfIn PDF document text
    • http://av-jet.ru/userfiles/file/6703961448.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210902020046331958il5zz7.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/likobuneduxuvagelifatof.pdfIn PDF document text
    • http://hmondo.com/userData/board/file/tujunogawivemijenizo.pdfIn PDF document text
    • http://kingkady.com/uploadfile/files/patasubolugelabezozase.pdfIn PDF document text
    • https://fu-ko-property-agency.com/webroot/editor-uploads/files/jubivepuwovumomo.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/jojawufofomanawavamemov.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/64342486374.pdfIn PDF document text
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/549c37517a1d967529f5eb2ac34a4352.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/40147433484.pdfIn PDF document text
    • http://chemicalengineers.ie/images/44981974613.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/09/11/file/20210911_160039_162.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/58171723058.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/suvaxezatoxiruna.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_off0001023c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011a53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A53 10636 bytes
SHA-256: a78b986d554968496b47707086b442979c40069053c6c40bee06b9cefbaf4169
font_02_sfnt_off00013295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13295 20384 bytes
SHA-256: 41bf7ddcb040f877a37fc3c9850b6825b088ecaed0ec9efd3df4c66043a25e5d