Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4b9c3901a4c89aa…

MALICIOUS

PDF

77.2 KB Created: 2021-02-09 18:14:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 63edd48e7813de195f74a46e86084a5e SHA-1: 6633d8a1449c521cc8f850ef7196f98212397236 SHA-256: f4b9c3901a4c89aa3e3cd72049f19bcb2379d3479f8c63929d59c728e60e6e1f
252 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to disposable domains and redirectors, indicating a link farm or SEO manipulation tactic. One critical heuristic identified links to known malicious redirector infrastructure. The ML classifier also flagged this PDF with high confidence, and ClamAV detected it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://yafferge.ru/123?utm_term=goanimate+for+schools+shut+down In PDF document text
    • https://cdn.sqhk.co/verexumifo/g6UgiQm/war_table_dragon_age_inquisition_hinterlands.pdfIn PDF document text
    • http://xubaseki.iblogger.org/2d_shapes_area_and_perimeter_worksheet.pdfIn PDF document text
    • http://gamokidawenikon.iblogger.org/73579802484.pdfIn PDF document text
    • https://bugedosase.weebly.com/uploads/1/3/2/7/132712019/lukod.pdfIn PDF document text
    • https://cdn.sqhk.co/ginudaket/L7JljeP/tibabosimalefirebizoz.pdfIn PDF document text
    • https://wegenagozej.weebly.com/uploads/1/3/5/3/135394478/vavupalebabi.pdfIn PDF document text
    • http://smotrikino.fun/dimimobogilemodidhtis1.pdfIn PDF document text
    • http://krokoboko6.xyz/65574810035ou4ou.pdfIn PDF document text
    • https://cdn.sqhk.co/gojikanemiju/jc5jbji/xezibazegojarimururod.pdfIn PDF document text
    • https://fusarutuzazeni.weebly.com/uploads/1/3/5/3/135346017/popefir-rixep.pdfIn PDF document text
    • https://cdn.sqhk.co/gajerivab/796high/dopivufenif.pdfIn PDF document text
    • https://cdn.sqhk.co/takularozo/chchdFp/noxozazubobowit.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://lisuxuzilim.epizy.com/rolixujo.pdfIn PDF document text
    • http://wowadowir.epizy.com/waco_texas_crime_report.pdfIn PDF document text
    • http://lotitivixuji.rf.gd/17939977848.pdfIn PDF document text
    • http://bewebumaxof.epizy.com/80247463238.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e2e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E5 5264 bytes
SHA-256: a7150d311049f313ca64bf18fee62c2bbf0b495e4cb4e9651fb1d6305e0c5e0b
font_01_sfnt_off0000f4a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A9 10740 bytes
SHA-256: fa5c877529be0bd696c459fa4e79ec0baa234b302493b81179140d42d89daea4
font_02_sfnt_off00011973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11973 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c