Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87ed43f2df52a28…

MALICIOUS

PDF

76.7 KB Created: 2021-07-16 11:45:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 219714575a59cbd8499fc27e119bcdbe SHA-1: 8dee6a5adfc53898938baaa0218cb448f110aa1b SHA-256: b87ed43f2df52a28ec9fac10aa9ea199d31ecdb26009924382bbae5a14910498
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. It contains an embedded URL that functions as an SEO redirector, leading to a phishing site. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the presence of a redirector strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6911

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://oniceh.ru/square?utm_term=postpartum+swelling+in+one+foot PDF link annotation
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60e8e3c48915684aa539b453/1625875396785/mac_preview_reduce_file_size.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60f0d3b16e9a9a494aa089a2/1626395569734/atypical_parkinsonism_psp.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60ed96fbc8312e4ee1ddcf1a/1626183419642/vowunosi.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60f0c0335554232196b694c5/1626390579778/24498542532.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_off0000c8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C5 10888 bytes
SHA-256: eb7419447b406d4b07dd873799b0c5a532e0d153a673ac6f1415216b743cc41c
font_01_sfnt_off0000e211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE211 16596 bytes
SHA-256: fd53f3656c30a93d1aa3aea8668ead6a7618e50bb55da81707a94b01b9e8fc3b
font_02_sfnt_off00010d5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1