Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a414c20dfa73648…

MALICIOUS

PDF

78.3 KB Created: 2021-04-05 07:40:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 92dc6604b0cdf3eaa9726830586254de SHA-1: bcf5a8d10ec2f501b697f95d672db173f13e2941 SHA-256: 3a414c20dfa7364846a90341490897620d43e7b02c077ecdc740091d91b378f3
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, with a significant number pointing to SEO-optimized redirectors and link farms, indicating a phishing or malware distribution scheme. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_UTM_REDIRECTOR_LINK' strongly suggest this intent. The presence of ClamAV detection and ML classification further supports the malicious nature of the file. Although no scripts were explicitly extracted, the structure and linked URLs point towards an attempt to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://baarspo.ru/award?keyword=haloalkanes+and+haloarenes+pdf+notes PDF link annotation
    • http://munasimowijuxi.getenjoyment.net/64691324691.pdfIn PDF document text
    • https://cdn.sqhk.co/namulofilox/xiDhcjg/vowebetojatetixuxov.pdfIn PDF document text
    • http://wapadax.scienceontheweb.net/nptel_biochemistry_notes.pdfIn PDF document text
    • https://cdn.sqhk.co/podoxato/sjjxifK/bubble_shooter_fruit_new_game_2019.pdfIn PDF document text
    • https://cdn.sqhk.co/foxoxaze/iajcTif/university_graduation_certificate_template.pdfIn PDF document text
    • https://cdn.sqhk.co/lilanoto/eibrhdA/buxakizuzelatuwevo.pdfIn PDF document text
    • https://cdn.sqhk.co/xejulonejo/gBhgjf4/new_york_city_recycling_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/meparifemoji/gijagc6/bessacarr_e425_manual.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/48fe569b-7f17-45b3-b643-1b789044ba61/veluberasaguravukoxovi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3d627194-09ca-4925-89ad-2ea8078f61f0/cisco_1841_router_configuration_guide.pdfIn PDF document text
    • https://2a50e20e-73b4-464c-af53-7ac4f68fee21.filesusr.com/ugd/7dd30d_be9ba159568646168b1f9967d5202dca.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/somamere/70777422546.pdfIn PDF document text
    • https://s3.amazonaws.com/xumakomowi/sarufupuvinuw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3943dfcb-8669-48b6-9e42-cf7de474cb12/momiwawutuwasimajazi.pdfIn PDF document text
    • https://2863666b-9d79-467d-9aad-9eeb6dafbdf2.filesusr.com/ugd/6ee3eb_6367c614d8f84b65b699378c185774fc.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rurosaveruk/nenunevoga.pdfIn PDF document text
    • https://s3.amazonaws.com/kubedukowug/92403158974.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ef40da01-75a0-46ca-bd23-8be99fd5a120/blood_of_elves_audiobook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9fcddbf9-9b1d-4a3b-b55c-d19192d6ccb1/3063739463.pdfIn PDF document text
    • https://s3.amazonaws.com/tiluwisulepam/17198161318.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5BE 5152 bytes
SHA-256: 1bebeb4c727de05d361b46ab9b05fd15111f9a65881c2bdd42ae9fb9417748a7
font_01_sfnt_off00010736.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10736 10744 bytes
SHA-256: 83df41b58df1b19dd9b27f96d62aa7b038fe88161fe16e5de837908a9bb11aa8