Malicious PDF — malware analysis report

Static analysis result for SHA-256 481d48477ac4fd8a…

MALICIOUS

PDF

165.0 KB Created: 2021-02-05 11:49:07 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-03
MD5: b1f30af7f5745f1eacf1142d54101443 SHA-1: 4f51896c2bc5384daeb5917f29fa3f1fef9935a9 SHA-256: 481d48477ac4fd8a8c0826649fefe4e0b6eba981672bc811423f2e2839fa8c8b
126 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains and link farms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body, though heavily obfuscated, contains metadata related to 'dissolved oxygen experiment lab report' and 'wkhtmltopdf', suggesting a lure to disguise the malicious nature of the links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 5

  • 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 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://jottigo.ru/aws?utm_term=dissolved+oxygen+experiment+lab+report PDF link annotation
    • https://cdn.sqhk.co/gawagunikuw/gc5iigW/pupakuluju.pdfIn PDF document text
    • https://cdn.sqhk.co/jutafegobexe/36Gjbgj/airbnb_app_login_problem.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500444/normal_5ff7a4bcb8c81.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4375698/normal_5fdca94b56525.pdfIn PDF document text
    • http://bluebadge-support.com/samoxuvotirovaleplrsc4.pdfIn PDF document text
    • https://cdn.sqhk.co/remigalakefo/gecjg0J/lovelace_westside_covid_testing.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373753/normal_601484656b77f.pdfIn PDF document text
    • https://cdn.sqhk.co/dedizajo/h1icihm/harpoon_winter_warmer_review.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4389581/normal_5fe3b56ab6c11.pdfIn PDF document text
    • http://rat-red.space/ganuxulagosadopobusirokes2cw7.pdfIn PDF document text
    • https://cdn.sqhk.co/madagijoj/heIigic/37430502563.pdfIn PDF document text
    • https://cdn.sqhk.co/difigobon/zajaWii/53400251945.pdfIn PDF document text
    • https://mafenipo.weebly.com/uploads/1/3/4/8/134879688/9784358.pdfIn PDF document text
    • https://cdn.sqhk.co/kixarozikej/5vQaaPN/puzabalemafazifudubesuzav.pdfIn PDF document text
    • https://nubeboganiroj.weebly.com/uploads/1/3/1/3/131384383/2398609.pdfIn PDF document text
    • https://cdn.sqhk.co/jasorevujoxu/RBeWoSL/algebra_1_final_exam_practice_test.pdfIn PDF document text
    • https://suwesinorilofev.weebly.com/uploads/1/3/4/0/134096988/4943733.pdfIn PDF document text
    • https://cdn.sqhk.co/lajoroteb/CuZ7gjm/spongebob_sponge_on_the_run_full_movie_dailymotion.pdfIn PDF document text
    • http://cocobeautybar.ca/graphing_polynomial_function_workshe85zo9.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/kagedatabujo/84831311253.pdfIn PDF document text
    • https://s3.amazonaws.com/xovekolamoxe/kapogimivaxomuzosodiren.pdfIn PDF document text
    • https://s3.amazonaws.com/bufexa/mejubodisisuwabigorumikaf.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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_off000229e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x229E7 6492 bytes
SHA-256: cf6bcbaf462759e04676f8989e7e87ed4d43c4317550ddbd0c5684ab0bd17b73
font_01_sfnt_off00023a1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23A1B 5648 bytes
SHA-256: 1dc99127bd4f02b189d5faa2716dd380125efcb2486a9490eb23e5b3db1ba8a5
font_02_sfnt_off00024d51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24D51 18020 bytes
SHA-256: 13e9ad0e9e718380fc249b98d57d4cee73140f259b0dfad04d35bd0c39128f5a