Malicious PDF — malware analysis report

Static analysis result for SHA-256 f63a12dd1388d058…

MALICIOUS

PDF

79.6 KB Created: 2021-07-13 22:20:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 49bc92c189e89ee5e159a086a249a411 SHA-1: 5ebc82cc36e35d4f9e320a7bfd7fda790be17208 SHA-256: f63a12dd1388d058570aece2c9c22de592fba50684902905b96d4d9d58ecf8f6
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, with heuristics indicating it's a phishing lure. It contains an external URI and an SEO redirector link pointing to 'https://oniceh.ru/square?utm_term=find+the+danger+within+saarthal+puzzle', which is likely used to lead the user to a phishing site. No scripts were extracted, but the PDF structure and heuristics suggest a phishing attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6556

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://oniceh.ru/square?utm_term=find+the+danger+within+saarthal+puzzle PDF link annotation
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60ec7aec0cf33f708d798423/1626110700239/how_to_find_domain_and_range_of_a_circle.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4e0d5abe22cec5c4b22/t/60ec8ed60f7d8d50062c97d1/1626115798754/core_java_collections_interview_questions.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60e8931b4374720c364efb81/1625854747618/29074630097.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_off0000d918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD918 10776 bytes
SHA-256: 6255e5574fbe617ce63039c556b43441fa1b03287ffd61cc4cbbc66c1536897e
font_01_sfnt_off0000f1a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A2 15888 bytes
SHA-256: 75e1e596006b8cfed7f8987b6f7abb4cacd937d157e675e19e38fe99b07a7518
font_02_sfnt_off00011a9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1