Malicious PDF — malware analysis report

Static analysis result for SHA-256 d492381276f3bbe4…

MALICIOUS

PDF

77.3 KB Created: 2021-07-14 04:37:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 5ba6d37cc56e10a2d66ccbfa52b7b950 SHA-1: 1879712dc4f232a11a7a31e562d07a48aeb47db8 SHA-256: d492381276f3bbe473db23f5daec2591512af210e6d5f9af7f463fa312223315
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains a heuristic firing for a redirector link, indicating a phishing attempt disguised as a free download. The ML classifier and ClamAV detection further support its malicious nature. Although no scripts were extracted, the presence of a redirector URL suggests an attempt to lead the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7939

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/v-xubMviL4Y/square?utm_term=the+pentester+blueprint+wiley+pdf PDF link annotation
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60ec90f0e0914637f38bef35/1626116336462/wemuzejisob.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60e912d6787dde1a90ad8870/1625887447081/android_set_screen_lock.pdfIn PDF document text
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60ee2981df3d323292cf249d/1626220929986/85147647293.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_off0000ce03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e61a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE61A 10716 bytes
SHA-256: 283ecf5b4a7ef45b96aea41ed02d52ef2438f493fc1d9e0e680b85505f764ca1
font_02_sfnt_off0000fe6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE6E 16160 bytes
SHA-256: 324daa3459119bf21918217c28270d8a656f91ad9907cb912503a817baa08dcb