Malicious PDF — malware analysis report

Static analysis result for SHA-256 d18aa65ec5fbef2f…

MALICIOUS

PDF

77.8 KB Created: 2021-03-23 09:41:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1c9d54efa33d3236f79b19dd261022de SHA-1: 58cc20b1f88802508d854c0db6f470b530d4dc5b SHA-256: d18aa65ec5fbef2f78efe2a13ebc24ea1b561538a49cc2c8713f89225b3b6301
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are disguised as relevant content, indicating a link farm or phishing attempt. The primary malicious URL, https://resalured.ru/123?utm_term=basic+english+test+for+employment+with+answers, is directly embedded and likely serves as a lure for users seeking employment tests. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://resalured.ru/123?utm_term=basic+english+test+for+employment+with+answers
    • https://vagibize.weebly.com/uploads/1/3/4/6/134618654/rogidorirebag.pdf
    • https://jopokoguse.weebly.com/uploads/1/3/0/8/130874396/2052627.pdf
    • https://tirepululavapiw.weebly.com/uploads/1/3/4/5/134576363/1246207.pdf
    • https://vorupegesozuzow.weebly.com/uploads/1/3/1/4/131453293/3328625.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/bisiku/which_language_is_used_for_iphone_app_development.pdf
    • http://zizokeb.rf.gd/antivirus_mac_free.pdf
    • https://uploads.strikinglycdn.com/files/e63b268c-3f12-4e68-810d-62e4382a6172/normal_distribution_z_table_calculator.pdf
    • http://nixasosuj.epizy.com/kruger_axial_fan_catalogue.pdf
    • https://uploads.strikinglycdn.com/files/67fec88e-0244-45cb-80b8-fad6e8936782/sims_3_cheats_needs_bar.pdf
    • https://uploads.strikinglycdn.com/files/b05ccf43-728f-4f13-adb6-24e355517331/lolutorafovewudibowomilij.pdf
    • https://s3.amazonaws.com/xijuxosisomuna/27971710567.pdf
    • https://uploads.strikinglycdn.com/files/1c1f6305-c322-4bf3-bc92-eb90da391944/what_happened_to_mary_anne_in_the_things_they_carried.pdf
    • https://uploads.strikinglycdn.com/files/a9e160bc-7d37-44c9-ab87-bba0c458497a/78934270430.pdf
    • https://uploads.strikinglycdn.com/files/b01f2408-ea6d-4b6f-bf8e-bc0fb7a863c4/kenmore_800_washer.pdf
    • https://uploads.strikinglycdn.com/files/27452bdb-dbc3-41bb-907b-f5aa4d86dfb3/80856216819.pdf
    • https://uploads.strikinglycdn.com/files/6251756c-5c8e-40fb-aa05-4ce4a349da52/35602995551.pdf
    • https://s3.amazonaws.com/midaguvimabof/the_ecology_of_plants_second_edition_ebook.pdf
    • https://s3.amazonaws.com/xezonijida/call_of_duty_mobile_obb_file.pdf
    • http://fereralud.epizy.com/set_law_2019_application_form.pdf
    • https://s3.amazonaws.com/bezutu/jemabojawelosoguxubobik.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e335.bin
726ff6834161af49c4fe4b6d5ba3bf5f26512d1b77e2a44f98ed6cfab16864d7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE335 5460 bytes
font_01_sfnt_off0000f5a0.bin
a31a12018ff5351a231a9d5fafa33a7ce41db16b0c2afd0cda3fecc0bbbe9448
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A0 11048 bytes
font_02_sfnt_off00011b34.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B34 4324 bytes