Malicious PDF — malware analysis report

Static analysis result for SHA-256 9853238778939985…

MALICIOUS

PDF

74.0 KB Created: 2021-06-14 07:01:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5dcf4d753b380a1084e0ce54f70cf0f7 SHA-1: 59bb39dca5d5b35d2e6b85e1912f4d5ea20f853a SHA-256: 9853238778939985e5e2267c5f49d6b51d2409b70906498e79c854f8bc14520d
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, a common tactic for link farms and phishing campaigns. The 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics indicate a deliberate attempt to create a network of links, potentially to manipulate search engine results or direct users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://crysiq.ru/pbw?utm_term=esl+teacher+cover+letter+sample PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4406789/normal_600fa4205719b.pdfIn PDF document text
    • https://donigulajerilag.weebly.com/uploads/1/3/0/8/130874297/4211098.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366351/normal_5fc844db0d2be.pdfIn PDF document text
    • https://mujavipaw.weebly.com/uploads/1/3/0/8/130874121/kuluveje.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477873/normal_6059d042ef4d5.pdfIn PDF document text
    • https://sofaruxilo.weebly.com/uploads/1/3/5/3/135309187/3760797.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391925/normal_5ff714393d5fd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384471/normal_6050bc1aa355f.pdfIn PDF document text
    • https://fozuxuvaporoj.weebly.com/uploads/1/3/1/8/131856883/ginebumalegajuwafa.pdfIn PDF document text
    • https://dibatavuxod.weebly.com/uploads/1/3/0/7/130775672/vebukibukuvere.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://defuveb.pbworks.com/f/bizubopumuvudo.pdfIn PDF document text
    • http://vawaguzidatu.pbworks.com/f/19873842359.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce76dac1-7c54-4700-9b30-390940c1e0bd/ez_go_powerwise_2_charger_repair.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ce5fd3d-4a74-49ea-b7ac-ed5d237c462c/how_to_install_onenote_2016_on_mac.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/07ff5550-2805-4676-870f-6beb59e749f8/gejozud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d718e7e5-4707-4556-819a-2d50c1899a3c/geologic_history_of_north_america_timeline.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/505fd202-0142-4949-af60-86f8269acf36/11718093608.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc1aa770-80aa-4f2d-b2d5-d9853e6a1a10/57839829136.pdfIn PDF document text
    • http://morabef.pbworks.com/w/file/fetch/144450882/20234670706.pdfIn PDF document text
    • http://gokuluxitup.pbworks.com/w/file/fetch/145275486/direct_and_indirect_object_pronouns_french_worksheets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/52782aed-b372-4ae3-8e83-cd37ab101f24/puwaxolokuxi.pdfIn PDF document text
    • http://kivupored.pbworks.com/f/318233320.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_off0000d7cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7CB 4824 bytes
SHA-256: 6214c944326362e8ef8d292f602b042f8e09e9284cb70ed2b5d0d2f1379abc8b
font_01_sfnt_off0000e82d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE82D 10772 bytes
SHA-256: b9cb7a57750bbfce4390bb5a8c75a314dbbe5fb56ae5e69aa622c331679656bd
font_02_sfnt_off00010c93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C93 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378