Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7c22f5b22cb6cb2…

MALICIOUS

PDF

74.8 KB Created: 2021-03-14 12:14:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-13
MD5: 96ad07fdcdf48c7e03b11236df1da4ee SHA-1: 414db68f87dbbaab01217a5f567ba58526a9896e SHA-256: a7c22f5b22cb6cb20aeed66ad6d12a8bebc1a84c4259e4996afd3328af6e2196
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content or phish users. ClamAV detection and ML classification strongly indicate malicious intent. The document body, though obfuscated, contains metadata related to 'wkhtmltopdf' and a keyword search, reinforcing the lure of a manual to mask malicious redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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.
  • 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://ponafet.ru/wix?keyword=klh+bassbite+v+subwoofer+manual PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4416927/normal_5fe4140ac317f.pdfIn PDF document text
    • http://jivusibofonefud.mygamesonline.org/llewellyn_set_dark_souls_2.pdfIn PDF document text
    • https://cdn.sqhk.co/jidelugob/Jjjdghj/2020_election_polls_fox_news_live_map.pdfIn PDF document text
    • https://fagovuwafarawa.weebly.com/uploads/1/3/4/0/134042706/bd05dd126.pdfIn PDF document text
    • https://cdn.sqhk.co/xavaxonad/4hhihXd/18797156989.pdfIn PDF document text
    • https://cdn.sqhk.co/wokiwife/hja4giI/54729269576.pdfIn PDF document text
    • https://cdn.sqhk.co/zabeluzitema/9hjhcbc/matudovakanisatod.pdfIn PDF document text
    • https://tusuwijajibu.weebly.com/uploads/1/3/4/5/134517525/3578323.pdfIn PDF document text
    • https://belogukuke.weebly.com/uploads/1/3/1/6/131637095/2dc4634740fae.pdfIn PDF document text
    • https://cdn.sqhk.co/futevanu/jjdjcM8/95719439.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465125/normal_5ff7d697875ab.pdfIn PDF document text
    • http://mutujejeturuduf.medianewsonline.com/3703728295.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/f8088448-809c-4aae-9096-b35a636c536a/hero_4_silver_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/64fef98a-87fe-4092-8f15-14610092e5db/90712258774.pdfIn PDF document text
    • http://pedirite.onlinewebshop.net/viron.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db8480fb-e94e-4171-bab2-22cde26f81fb/kusewuf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/25507cf3-efe8-48a7-9f92-6faad3746361/82758518098.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/48c281ad-eca6-4d24-83fe-20078adb2a0c/projective_geometry_and_its_applications_to_computer_graphics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f0f0bf2-e7e8-4e03-bc77-9e14b15d9125/46919773777.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af7f87fa-ad0f-4dc1-bb82-560e6528671c/widudutusakudukisa.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_off0000dc3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC3E 2900 bytes
SHA-256: a28fcc4ba65d8171a55e8b87d646ac5d1dd213f66ab2b0026fd39e5ca5d32d1a
font_01_sfnt_off0000e680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE680 5268 bytes
SHA-256: 8e92fb73bf589d4826e3e863e6c58f31b9fb8d6de9de17cd51d3b1adf588d3b6
font_02_sfnt_off0000f85d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85D 11152 bytes
SHA-256: 421c99a299130eb4efd61b47551f852950496af162839e472b2f266a25244aea