Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9ce6dd528f8157f…

MALICIOUS

PDF

68.5 KB Created: 2020-11-20 13:47:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: f8a9efa910b89bfdaf0cf4e21a2aedb3 SHA-1: efb41d1cf0bef9c83e8374199f24aa224f0fac04 SHA-256: a9ce6dd528f8157f34b9b82dfef2445ac6a01ed3c4fb83d591393c3ad66a9324
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, many of which are part of an SEO link farm designed to redirect users. One prominent URL, 'https://trafffe.ru/123?utm_term=better+vampires+please+feed+to+update', is identified as a redirector, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly indicate malicious intent, consistent with a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://trafffe.ru/123?utm_term=better+vampires+please+feed+to+update PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366374/normal_5fa1ce909827f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367667/normal_5f886fbfd4fd7.pdfIn PDF document text
    • https://dejolezeg.weebly.com/uploads/1/3/2/8/132815968/add8f8094b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375350/normal_5f91f882a24bf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367687/normal_5f8b0a9e8b7c9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368466/normal_5f8e396644212.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/68f98fbb-202e-4c59-bcd1-011d5312ed3c/infinity_wedding_band_rose_gold.pdfIn PDF document text
    • https://s3.amazonaws.com/zuxadol/21424039904.pdfIn PDF document text
    • https://s3.amazonaws.com/welutizenop/actor_paul_stevens_biography.pdfIn PDF document text
    • https://s3.amazonaws.com/roxawo/w3schools_html_forms.pdfIn PDF document text
    • https://s3.amazonaws.com/mipeboro/themes_in_the_secret_life_of_bees_movie.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18d818de-c184-42b1-ae0a-91734a4f994b/74297187722.pdfIn PDF document text
    • https://s3.amazonaws.com/kubafezin/la_grande_odalisque_ap_art_history.pdfIn PDF document text
    • https://s3.amazonaws.com/nabifovu/1316016475.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD9B 5296 bytes
SHA-256: b2be4613d3a1021b713dccf49c2a75a043bbb3dd5b72f0a294b22cebcde362f9
font_01_sfnt_off0000df8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8D 10992 bytes
SHA-256: 4096d39b4191103b3b811b6275db802c4fa8d31270cdce15b2af303865013b7b