Malicious PDF — malware analysis report

Static analysis result for SHA-256 86669140d0803c69…

MALICIOUS

PDF

80.5 KB Created: 2021-07-13 00:32:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c0ef2c898ec7b498d35b464eb1b16ceb SHA-1: 976d76a4d671a025a5efa57ea522c0217f283749 SHA-256: 86669140d0803c69900deef8cc8d3e84c70fd280f751253d2c2e3cc9ae973ebc
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The file is a PDF document that contains a lure for a free download, indicated by the PDF_SEO_UTM_REDIRECTOR_LINK heuristic. This lure redirects the user to a URL that is likely part of a phishing campaign. The ML classifier and ClamAV detection further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6556

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
  • 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://feedproxy.google.com/~r/sq/ugae/~3/UkUWPC8UKDU/square?utm_term=stage+1+disciplinary PDF link annotation
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60e951e4f492d21a0f6c554c/1625903588524/stoichiometric_chemical_equation.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60e91af73f195e1e4036248f/1625889527321/the_expendables_1999.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6cad3a95e91b59aa2418/t/60ec7f62ef188817f7e0fbe5/1626111842483/48818870685.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_off0000d8eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EB 10808 bytes
SHA-256: 0b7c3f6b3c07b6707155cf80b5140aae3f086c65d39d572ca5e0a5e73554c4df
font_01_sfnt_off0000f1cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DE 16688 bytes
SHA-256: 3f991b31272997c6aa6d6ad550147458371f6d02d4ada3969471044c8be972d8