Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ad44fd1878c60b7…

MALICIOUS

PDF

75.7 KB Created: 2020-12-27 14:50:01 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f4bc2124ba8f8f695f3a752f8a14267c SHA-1: 7a1ab48dcf877ff570d06638fa39acfe4f581293 SHA-256: 8ad44fd1878c60b79b351339d4a03796c993f4c161ff7e230a8b68f909bf7309
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious Link

This PDF document is identified as malicious by multiple heuristics, including a critical ClamAV detection and an ML classifier. It functions as a link farm, directing users to various external URLs, one of which is associated with a scam lure. The primary attack pattern observed is an advance-fee scam, leveraging deceptive content to trick users into clicking malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Advance-fee lottery/parcel scam lure high SE_ADVANCE_FEE_SCAM_LURE
    Document contains lottery/beneficiary or prize language together with large-value draft/funds wording and parcel/courier delivery requirements. This is a classic advance-fee fraud document shape.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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/strik?utm_term=free+gay+chat+dating+sites+uk
    • https://cdn-cms.f-static.net/uploads/4369504/normal_5faa2045d4bea.pdf
    • https://riwominejakubik.weebly.com/uploads/1/3/4/5/134598273/7c76b55c3a866.pdf
    • https://melegejisud.weebly.com/uploads/1/3/1/3/131379421/dewuvatagulil.pdf
    • https://tabupuja.weebly.com/uploads/1/3/4/6/134647436/7986182.pdf
    • https://static.s123-cdn-static.com/uploads/4408599/normal_5fe31219d7abc.pdf
    • https://cdn-cms.f-static.net/uploads/4365661/normal_5f86f79e52b86.pdf
    • https://cdn-cms.f-static.net/uploads/4423136/normal_5fb74d60c8429.pdf
    • https://jikeberu.weebly.com/uploads/1/3/1/8/131857846/kubowirokaxub.pdf
    • https://fodezamu.weebly.com/uploads/1/3/1/4/131407453/1000608.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/7c406ab4-8c6f-4a20-9b93-c9a410fede7c/woxevegebeja.pdf
    • https://uploads.strikinglycdn.com/files/a9486d73-088b-4ac3-9ad3-5c9b4ccdddd6/eic_worksheet_b_form_1040.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dde5.bin
8aa988fb0bdb41ff3a1664b0ac8c270a5189cc12fcfb2ed3a1ee7b4fc54d1b7d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDE5 5060 bytes
font_01_sfnt_off0000ef14.bin
b6a492168495b7d4af8455520af3dbdc9d7c3a56369b25563a7c10d0f76630c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF14 10780 bytes
font_02_sfnt_off00011385.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x11385 4324 bytes