Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aab233b3d18d086…

MALICIOUS

PDF

76.6 KB Created: 2021-04-16 20:23:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 534326163d1ed5b4dd577f62bf869f23 SHA-1: 6a149c3321c2666e65d46ff5f1311167a5c9dc2c SHA-256: 4aab233b3d18d08696175b163cdd9e217c9abb02dcdcaa6850e3ff73d8200043
126 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous embedded URLs pointing to disposable hosting and link farms, indicating a phishing or malware distribution attempt. The document body, though heavily obfuscated, suggests it is disguised as educational material to lure users to these external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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 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://pelibifir.ru/strik?utm_term=aguda+llana+o+esdrujula+ejercicios PDF link annotation
    • https://gosasolana.weebly.com/uploads/1/3/4/5/134523876/8b51d4b1a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470211/normal_606396a1ccf97.pdfIn PDF document text
    • https://paxituzupinemof.weebly.com/uploads/1/3/5/3/135303349/3478083.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414172/normal_5ffcf3a0c76ec.pdfIn PDF document text
    • https://cdn.sqhk.co/poraloguve/hhhfjfK/uc_browser_java_9._5free.pdfIn PDF document text
    • https://cdn.sqhk.co/tezuzerise/0qT9wlM/download_magic_school_story_mod_apk_unlimited_money.pdfIn PDF document text
    • https://cdn.sqhk.co/xivovido/NVdWPhg/vemegozajadexemimewi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4469860/normal_5fe5b1781c1b5.pdfIn PDF document text
    • https://guzifako.weebly.com/uploads/1/3/4/0/134096492/c7362700c.pdfIn PDF document text
    • https://cdn.sqhk.co/levowexesu/ihiOeUO/99080323939.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446762/normal_5ff905fd43132.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445742/normal_5fd644ee3e3b6.pdfIn PDF document text
    • https://gexemuxu.weebly.com/uploads/1/3/5/3/135394015/5805651.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414849/normal_60417bccd142f.pdfIn PDF document text
    • https://femobideja.weebly.com/uploads/1/3/4/7/134735935/1579896.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481062/normal_6044ad5cb13a3.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/e8d3688c-1b50-4c84-8ca4-84374f152612/kifazidi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f12a3699-7690-4d6b-a846-55f24299145d/political_philosophy_podcast.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f1e2868f-0c6b-4eda-9bf1-83949e11df2a/do_wendys_spicy_nuggets_have_egg.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a7581163-e221-4724-97b0-30f8abc10027/5th_grade_math_book_mcgraw-hill.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/256c08c7-9abd-48ae-940f-1369f312b70a/digital_integrated_circuits_a_design_perspective_second_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7593f0e-7ead-41e2-80a0-c0571974ddea/convert_mp3_to_musicxml_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/daf4f6d5-6cfc-43eb-9ab6-a911019166b7/love_poems_for_your_long_distance_girlfriend.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9DE 5172 bytes
SHA-256: 878d6431820d51118eddd780e2e7a3294bf0fc82ecbc227249f91b94a9cfb78a
font_01_sfnt_off0000fb8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8C 12460 bytes
SHA-256: 61042a147388781c1a209dd14ff31e1cbab3758c245e3c8c6088c86faf23bd9a