Malicious PDF — malware analysis report

Static analysis result for SHA-256 1df956af1a311d44…

MALICIOUS

PDF

89.1 KB Created: 2021-09-16 22:07:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8e1e584d4a0dbc192f522b3287ea2b30 SHA-1: 41086931879a4d19561c94881667d3b96b2058ef SHA-256: 1df956af1a311d44c7237df63ad43bc92e5ca767522b0bbf19123f0e3e0427d7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and links to compromised CMS uploads, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded links are designed to lure users to external sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://synerhu.ru/uplcv?utm_term=pokemon+fire+red+download+ios PDF link annotation
    • http://fioredda.com/userfiles/files/53601146356.pdfIn PDF document text
    • https://nawaasha.org/userfiles/file/mapuribulapewak.pdfIn PDF document text
    • https://global-brand.net/userfiles/files/65675588227.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133201162d5e---76383570169.pdfIn PDF document text
    • https://vadihosting.com/calisma2/files/uploads/sazofimowa.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/saxuxibobebijomevaburubi.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137fddcabe91---98883748931.pdfIn PDF document text
    • http://austria-ex.com/images/blog/file/tujiju.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613957419efd5---subilonafeviwuzebokijen.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/161434d824985e---73890559707.pdfIn PDF document text
    • https://civilkontroll.hu/uploads/file/lidoni.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109100843397957.pdfIn PDF document text
    • http://grubstreet.ca/ckfinder/userfiles/files/78422400824.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109031400286043.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/90084175218.pdfIn PDF document text
    • http://salsainkonstanz.de/media/files/sofeg.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/morimalefojuk.pdfIn PDF document text
    • https://vwb.mrv-educationservices.com/content_file/files/1453690988.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/jivokimidosifusemorip.pdfIn PDF document text
    • http://sokole-tps.pl/userfiles/file/38810870089.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/7517854141.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_off0000f131.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF131 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10948 10596 bytes
SHA-256: 7a7d1d109b0a95b1addf87e335bee8eb25671b3f7e3742faf05af901729a2f5a
font_02_sfnt_off0001217c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217C 20220 bytes
SHA-256: b39287eccb2c1a2f2ccb5a605b44b448f5e7c282abb5f6c23a3fa30bc95bd3e2