Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6da4d56bfabd3cb…

MALICIOUS

PDF

74.5 KB Created: 2021-05-29 04:58:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 95bd224653af7cd5d26a5c46bc187a9d SHA-1: 7f399794dc7001c4682be29ef66c8798267fa698 SHA-256: a6da4d56bfabd3cba41af002d63e6be40e6628c592167a2bc492417a2dc35289
216 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to SEO redirectors, suggesting a link farm or phishing lure. The presence of embedded URLs and the 'SE_CALLBACK_LURE' heuristic further support a phishing or scam-related attack pattern. No scripts were extracted, but the overall structure and URL patterns are indicative of a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) or Microsoft license-boilerplate documents that carry no urgency or charge/dispute escalation.
  • 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://leonvi.ru/strik?utm_term=foxwoods+restaurants+buffet PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4415052/normal_5ffeb24cdd1bf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476582/normal_5fd281391b554.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426071/normal_5fda6a6863423.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449776/normal_602e4afc8dcce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366024/normal_603edf37cd54c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379968/normal_602f1404e155c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391340/normal_602da2b00cb6b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500001/normal_5fe4ffcb837df.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475565/normal_602ec0e2e4f61.pdfIn PDF document text
    • https://mizujaketoki.weebly.com/uploads/1/3/0/7/130776151/8865580.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4415754/normal_5fdd9c48d4e68.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4422161/normal_5ffa3fa17d34b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447880/normal_5fdde1b355b08.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413223/normal_5fcecee01d9e5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413126/normal_604fe53a8fa7a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393036/normal_60205fe504991.pdfIn PDF document text
    • https://wasexakenisopi.weebly.com/uploads/1/3/5/9/135982815/2230123.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369777/normal_6054040a1a2bd.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000e25b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE25B 5124 bytes
SHA-256: e79b393a869715214c6d31c7a42f984d14bd24ebd4bb7d79bfa1c8bb5168f8e0
font_01_sfnt_off0000f3ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EC 12188 bytes
SHA-256: add15c0cbfb8a62470c3aa1171f08fe27dd144d39c4669a3f1dd96707d76c1fc