Malicious PDF — malware analysis report

Static analysis result for SHA-256 a16bcd696a291a60…

MALICIOUS

PDF

72.9 KB Created: 2021-07-13 22:41:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 7dc1f50f161261944e70594988472a92 SHA-1: eb4e509a38a448723d11535faaca013f530f6bbe SHA-256: a16bcd696a291a6046e47fb4696d687c6abc6bc48d2e3afe86c5f488afbf72ef
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of an external URI and an image lure linking to an SEO redirector, suggesting a phishing attempt. Although no scripts were extracted, the PDF structure and heuristics point towards a malicious intent to lure users to a potentially harmful site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6193

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://feedproxy.google.com/~r/sq/ugae/~3/UkUWPC8UKDU/square?utm_term=do+rhododendrons+do+well+in+shade PDF link annotation
    • https://static1.squarespace.com/static/60aac4e0d5abe22cec5c4b22/t/60e8334685664d35b0eb1e42/1625830215055/what_does_gratitude_mean.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac5994c6b1805bc4acbdb/t/60e862c60997f07e4a745f6d/1625842374651/44105574864.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60e7d289bab0621613380881/1625805449219/persona_2_innocent_sin_psx_iso.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60ec9cd87b14134336defa8b/1626119384240/leduwenet.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_off0000bef1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEF1 10336 bytes
SHA-256: 800a683935a07e8b91aae5c9de3cfe05b85ca473efda881f2e459825e5909a24
font_01_sfnt_off0000d62e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD62E 16208 bytes
SHA-256: b2afbcb4e0fcf4f9e8b5d6ff655a367418a7a6e65824f7fb7b9e51b9ced9c512
font_02_sfnt_off0000ffed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1