Malicious PDF — malware analysis report

Static analysis result for SHA-256 460ea13835416e84…

MALICIOUS

PDF

80.8 KB Created: 2021-06-03 18:09:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 008b0e5186b50b7f6e4de1fb3b434052 SHA-1: 2f558144bcbc05f3c12c06facb3ca73700a3c6cc SHA-256: 460ea13835416e84c120025f86a3bd9cbb96bee5f72be56e5d3ec54295f82100
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many hosted on disposable domains, suggesting it functions as a link farm designed to redirect users to potentially harmful content. The document body, though heavily obfuscated, appears to be a lure related to 'letter writing format'. No scripts were extracted, but the PDF structure and numerous external links point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://dugedepap.ru/123?utm_term=letter+writing+format+in+english+to+principal PDF link annotation
    • https://vejiledulibona.weebly.com/uploads/1/3/4/3/134318828/nibenob-gudetosobipopo-dunisijeti.pdfIn PDF document text
    • https://tofixotiz.weebly.com/uploads/1/3/4/6/134621190/kajikilor.pdfIn PDF document text
    • https://lutitisuputusi.weebly.com/uploads/1/3/1/4/131437948/9892138.pdfIn PDF document text
    • https://xifamileg.weebly.com/uploads/1/3/4/6/134687686/5167399.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370078/normal_5fdb6ee6bf616.pdfIn PDF document text
    • https://bijuxoku.weebly.com/uploads/1/3/4/9/134901677/cac19a247652.pdfIn PDF document text
    • https://rigugoxa.weebly.com/uploads/1/3/0/7/130776225/8860650.pdfIn PDF document text
    • https://lukigozijejis.weebly.com/uploads/1/3/5/3/135398738/51484400.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489980/normal_603c1335ebe94.pdfIn PDF document text
    • https://xoselupovogim.weebly.com/uploads/1/3/4/6/134610719/bixajatigonoxag_denizijexiw_zilizanodibeve_bajupiralowo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378608/normal_5fd08b12877c1.pdfIn PDF document text
    • https://nepuvojikonutoz.weebly.com/uploads/1/3/4/6/134677469/cbf38b84.pdfIn PDF document text
    • https://zupeloniz.weebly.com/uploads/1/3/4/0/134018773/tasizigafanoli.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422136/normal_605c91f9ba03a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369316/normal_605c8c7744807.pdfIn PDF document text
    • https://rosuxemu.weebly.com/uploads/1/3/0/7/130776582/3430949.pdfIn PDF document text
    • https://zivumabozado.weebly.com/uploads/1/3/4/8/134858695/nefokataketivaf_zobat_misazugos_mosepafuvaxu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tujedet.pbworks.com/f/bunegej.pdfIn PDF document text
    • http://jiboduxoguv.pbworks.com/w/file/fetch/144506742/55219389193.pdfIn PDF document text
    • http://jesababa.pbworks.com/f/venn_diagram_questions_and_answers_in_english.pdfIn PDF document text
    • http://xifatarege.pbworks.com/w/file/fetch/144555462/jilunaw.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_off0000ff0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF0B 5460 bytes
SHA-256: b05a36d7545034579e9ee7f5e871b34ff6070d4ed331fa6b5bad75e63dbb6932
font_01_sfnt_off00011191.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11191 10664 bytes
SHA-256: cb11f656ff70e23880d49480f38aec323e78c13886c669f8b4f565cbc766619d