Malicious PDF — malware analysis report

Static analysis result for SHA-256 891ce82fa16df154…

MALICIOUS

PDF

87.4 KB Created: 2021-03-07 23:58:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 6b4df54c09bf81e14ff4273dbe8af3ae SHA-1: 6a086fe5ff9ab5bf94e530f0901c09a61ee558d4 SHA-256: 891ce82fa16df154c6af37d747f7a7e82906842d3a21ad7595e2fa4b2d0b31e7
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing and trojan activity. The embedded URLs and the structure of the PDF point towards an attempt to redirect users to malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://zajinet.ru/strik?utm_term=ejercicios+de+probabilidad+y+estadistica+resueltos+variables+aleatorias PDF link annotation
    • https://febapemideb.weebly.com/uploads/1/3/0/7/130738739/nubanobekoma.pdfIn PDF document text
    • https://divevuke.weebly.com/uploads/1/3/3/9/133999966/zijipanutepomaxi.pdfIn PDF document text
    • https://xewulatejema.weebly.com/uploads/1/3/5/3/135345986/natorapumuwu.pdfIn PDF document text
    • https://xufolonul.weebly.com/uploads/1/3/2/6/132695880/xapasa_wapifazuvivuti_jixozisidajal_juwaxesite.pdfIn PDF document text
    • http://bipiraxas.iblogger.org/xenoluxovamupo.pdfIn PDF document text
    • https://cdn.sqhk.co/pobumepova/lRjb1nC/proloquo2go_switch_scanning.pdfIn PDF document text
    • https://sonalopuxarore.weebly.com/uploads/1/3/4/3/134310538/nubujakox.pdfIn PDF document text
    • https://radetotoko.weebly.com/uploads/1/3/4/6/134697609/8393723.pdfIn PDF document text
    • https://medizagokitoni.weebly.com/uploads/1/3/2/3/132303310/xizasififuveteru.pdfIn PDF document text
    • https://wujibinofowe.weebly.com/uploads/1/3/1/3/131383737/wurevagub-nifekitojaled-gajex.pdfIn PDF document text
    • https://cdn.sqhk.co/jawefujivi/fhcgfqs/5216928111.pdfIn PDF document text
    • http://janafan.scienceontheweb.net/82967209201.pdfIn PDF document text
    • http://fijexojor.getenjoyment.net/volvo_penta_sx-m_outdrive_oil_change.pdfIn PDF document text
    • http://dimoduves.22web.org/kitchenaid_mixer_repair_manual.pdfIn PDF document text
    • http://bebetadiruj.mywebcommunity.org/kivarefoxegavowikeb.pdfIn PDF document text
    • https://gamalisixidu.weebly.com/uploads/1/3/5/9/135958628/bogevepurit-mosejenitex.pdfIn PDF document text
    • https://cdn.sqhk.co/fafujedajir/yR3hdCa/rujatolewadizabutexuxo.pdfIn PDF document text
    • https://waderiraxobo.weebly.com/uploads/1/3/4/5/134505054/jifas-zumunasa.pdfIn PDF document text
    • https://cdn.sqhk.co/mukibusu/imhc4DI/biriwodu.pdfIn PDF document text
    • https://cdn.sqhk.co/betewulo/RVpGhem/scorpio_car_racing_simulator_mod_apk.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/2973729a-0242-4de9-9be2-92ee3aa3b8aa/student_bio_data_form.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/56dfd9b8-0ae6-4688-a786-4f48e29b0d75/wahl_clippers_instruction_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb0e865d-ddb6-4428-83f0-30c66a4df1ce/60724122412.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5aa2294-00ed-4b89-8b77-4c1a4087a94d/best_maths_book_for_class_6_cbse.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f31f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF31F 5400 bytes
SHA-256: 878b01fbae20f72c1ca438496bb7b07ae0cd9276aa7b2de9f3daad3c9d4ef9c5
font_01_sfnt_off00010598.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10598 13228 bytes
SHA-256: f8122b73b1006f3906df41629a9d2ee6c703b9af71e8f2b1d2ec1bc23ec3071d
font_02_sfnt_off0001318e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1318E 18348 bytes
SHA-256: 0d7739c3c56d182b478b2b004dcccd77da2e91d9edef802d05cb66f214a173e6