Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea8e0d87253a41db…

MALICIOUS

PDF

77.1 KB Created: 2021-07-17 03:39:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 6cbac39da2c0f7f55b16d81a39daf122 SHA-1: 26b6888fc865e1f0cee92986c0567de696f95d42 SHA-256: ea8e0d87253a41db2130c6940fdf01dcd6eb557f5016f90af5ebc91182ffa7be
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers indicated maliciousness. It contains an embedded URI and an image lure that redirects to a Google feedproxy URL, which is a common tactic for phishing or malware distribution. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not a legitimate document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7604

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/~3/7R6buoffwiA/square?utm_term=report+power+outage+in+my+area PDF link annotation
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60edde3310369373fd83ecea/1626201651399/34727375955.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6c89a2b0b938881bcf91/t/60f120c82606b657d356d23e/1626415304929/micturating_cystourethrogram_radiology.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60f090112f7a093491a21679/1626378258147/bsci_code_of_conduct.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_off0000cdfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDFD 10728 bytes
SHA-256: 974c35f1ff96c69925b236406854dd636e3979466b1ea5cbcdcfd5dd2aef3f50
font_01_sfnt_off0000e6a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A6 16264 bytes
SHA-256: c3fbad4aa72463955c500e814a2a447993d1a0ceea8c6e633ec1394625f94eea
font_02_sfnt_off00011095.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11095 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1