Malicious PDF — malware analysis report

Static analysis result for SHA-256 25c4a9fd7cdbbf61…

MALICIOUS

PDF

69.1 KB Created: 2020-11-24 17:53:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: cf6513f115655710ce4964ab607b9c0a SHA-1: b59795b5ac1064592fa291dc5192ad708f7ed036 SHA-256: 25c4a9fd7cdbbf61cd41a36ab88ab706ed916c63088408c76e44da6dfffb3e9c
314 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains multiple heuristics indicating malicious intent, including a critical finding for a brand-impersonation credential phishing lure for Yahoo. It also links to known malicious redirector infrastructure and a large number of external PDF links, suggesting a link farm or SEO abuse. The ML classifier strongly flagged this PDF as malicious, and ClamAV detected it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://fesoviso.weebly.com/uploads/1/3/4/7/134710514/f97b72bd0a19eaf.pdf.
  • 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.
  • 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://cctraff.ru/aws?utm_term=tv+guide+magazine+online In PDF document text
    • https://cdn-cms.f-static.net/uploads/4494431/normal_5fb65fffe9717.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418381/normal_5fb59a6fc83ff.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368740/normal_5f91581235e85.pdfIn PDF document text
    • https://fesoviso.weebly.com/uploads/1/3/4/7/134710514/f97b72bd0a19eaf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424682/normal_5fa951ed2128e.pdfIn PDF document text
    • https://lebotuzipum.weebly.com/uploads/1/3/4/5/134519329/rogananovetobi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453338/normal_5fa293c130274.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412908/normal_5fb587bc6c303.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/0213b875-58f6-44f0-9eb3-37a2307ac0bc/miraruxugoluguf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d3ba419-b7fb-44e7-9faf-290dafe45091/7691971217.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9f166c2-9871-4645-b00b-e1ade5a98453/ups_infonotice_number_format.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc3f3f8a-a9cd-470e-91c8-7b362a85740b/xuletoxorenesojise.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_off0000d2d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2D3 4928 bytes
SHA-256: 7fa7d31c3e21d9477a2eea4d4bbf629ee69b1ed748f3d58c5720e299377006ae
font_01_sfnt_off0000e397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE397 10644 bytes
SHA-256: a9e03fcda62e0dc06c4b024ae838b9e95127a569077b9e0e3eb04c9342e27673