Malicious PDF — malware analysis report

Static analysis result for SHA-256 f687ce0b2c4008c1…

MALICIOUS

PDF

81.7 KB Created: 2021-07-14 06:10:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b42b527109a01dbf2654cf7a4e93e58e SHA-1: aebfedd3726f22bcd4c0e675717072cc2fb6eadf SHA-256: f687ce0b2c4008c146bc46bc407ace5fe733124c626cf38f8995037a59ef0319
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated maliciousness. A high-severity heuristic identified an image lure linking to an SEO redirector, specifically the URL https://feedproxy.google.com/~r/sq/ugae/~3/jEScUJLm1bs/square?utm_term=top+ten+busy+airport+in+the+world, which is indicative of a phishing attempt to trick users into downloading further content. No scripts were extracted, but the overall structure and heuristics point to a phishing attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6221

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/jEScUJLm1bs/square?utm_term=top+ten+busy+airport+in+the+world PDF link annotation
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60ecb5a66de3926792abc331/1626125734078/activity_1.2_3_electrical_circuits_simulation.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4e0d5abe22cec5c4b22/t/60ecb218635fe735bd7ec601/1626124824897/counting_phonemes_worksheet.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e8f6e0e6bd1231e6062d26/1625880288822/47020283879.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_off0000dd04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD04 17240 bytes
SHA-256: 06fbfc9e330ab302cbdcacf290ad831b60436612ff639e6ada25288d3a22034c
font_01_sfnt_off000109f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001220f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1220F 10892 bytes
SHA-256: 830be6b1511af2ec9da74dff7dcd0fe2334c40478b367313f75a069095763334