Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c756bb34f10f84…

MALICIOUS

PDF

73.3 KB Created: 2021-07-13 22:10:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 065425afc747015fd9fd611045a64d12 SHA-1: c8aa227a4318b1ed46f463cfe5b3dff60ecc7fce SHA-256: 88c756bb34f10f84f679f5f5402a3865881a35369ad2242ce3c20815bddb38cb
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers also indicated maliciousness. The 'PDF_SEO_UTM_REDIRECTOR_LINK' heuristic indicates the document uses an image lure to redirect users to a phishing site. While no scripts were explicitly extracted, the PDF structure and heuristics suggest a phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7185

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/RVI1sXQGPkU/square?utm_term=different+industry+sectors PDF link annotation
    • https://static1.squarespace.com/static/60bf6c89a2b0b938881bcf91/t/60e805ad1c6ee137fa1285bc/1625818541523/easy_stuffed_cabbage.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60e9317b5fa2eb14b90c5d88/1625895291096/xosiruvofamifezejo.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e77dd5fa94092a577bab51/1625783766079/19664846826.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_off0000be11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD623 16704 bytes
SHA-256: 066aaec3946815e9ba57084f6372de74d89aa6dc1c9c3efde4e6e7d1f01b1a1d
font_02_sfnt_off0001018f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1018F 10476 bytes
SHA-256: 72aec4362cb2b8b513be9ee6056c61a0fcce91a899ac8c757a69472dbb0dfbbc