Malicious PDF — malware analysis report

Static analysis result for SHA-256 b62d2851131b66c6…

MALICIOUS

PDF

76.8 KB Created: 2021-07-13 18:35:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 84e35b08a96a827668aedf7e6d6f4116 SHA-1: 6b9af9a49dd27933560486bc1ccdf84f3a623702 SHA-256: b62d2851131b66c67b05ffae38d13eb6a20bc715db32395f2a4318ac4e96db83
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of an external URI and an SEO redirector link, suggesting a phishing lure for a free download. The document body is heavily obfuscated, preventing a clear understanding of its direct content, but the overall pattern points to a phishing attempt.

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/razvivatel/yapz/~3/UkUWPC8UKDU/square?utm_term=how+can+i+get+minecraft+on+my+chromebook PDF link annotation
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60e7bbd6a431ed42d2fa3aeb/1625799638500/69749299692.pdfIn PDF document text
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60ed5d4e3489b768f16fd46e/1626168655124/61879807931.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e83cfe9e539748b118d639/1625832702524/fopezukolojonukerupe.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_off0000cb63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB63 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e37a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE37A 10992 bytes
SHA-256: de08088932bae8ce908fa85c6131e473ae4f2997efd6cac3d7dd5c4363de2f7f
font_02_sfnt_off0000fcdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCDB 16632 bytes
SHA-256: 6743a049c7fe53a113f120459b1665766b3d1f8271861aae85a53b6dee644b6c