Malicious PDF — malware analysis report

Static analysis result for SHA-256 a50fa21fc89d7b0c…

MALICIOUS

PDF

79.8 KB Created: 2021-07-13 16:06:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 306ac58cf638208ce723861abc63ac3a SHA-1: ff4b0ec37a98c761198e6f58f34cd61b35e06058 SHA-256: a50fa21fc89d7b0caf79944c853c44eeac1b8fc025f6f99692dd1cb8c7a42a08
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains heuristics indicating it is a phishing lure, specifically using an image to redirect users to a malicious URL. The ClamAV detection and ML classifier further support its malicious nature. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to trick users into visiting a phishing site.

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/razvivatel/yapz/~3/XMoLd4EPXkg/square?utm_term=whistleblowing+on+your+boss PDF link annotation
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60ec9dd3f4b4775d04a1960c/1626119635452/xujewav.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e774bd5a6a8d4024560563/1625781438073/94282768607.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60ed8e0af84adf285bf4620c/1626181131020/nuzumejupelel.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_off0000d80c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD80C 16212 bytes
SHA-256: 8cfc8a895da2a7f98bf3b80d2f2e7d978e62300b48ba4ba0d67ab5850aacfba4
font_01_sfnt_off000101bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000119d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D2 10656 bytes
SHA-256: 0ce9ee89b7e6ac0e80e86a32ac20a46f29a5100ee1c2f3e8ed8b7fd24d1fd630