Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd88230fb283ef35…

MALICIOUS

PDF

122.4 KB Created: 2021-04-21 01:58:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 7d18518121042de42065c84369af1f98 SHA-1: 21b60fc895b669328141f92970040bd2ece9bf14 SHA-256: dd88230fb283ef35cd91f384c33a92939820b8505d901bcd26a4d52f4849914b
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many pointing to disposable hosting, indicative of a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://xezojetit.ru/strik?utm_term=aqa+gcse+physics+equations+quizlet PDF link annotation
    • https://vugevosuza.weebly.com/uploads/1/3/5/3/135328642/vebezub_xukuxi.pdfIn PDF document text
    • http://sumigemag.mywebcommunity.org/vopalivabekonidilokakufet.pdfIn PDF document text
    • https://vukumurumijolot.weebly.com/uploads/1/3/4/4/134433046/fosuvoviduna_xukewo.pdfIn PDF document text
    • http://kajipim.mypressonline.com/abdomen_anatomy_questions_and_answers.pdfIn PDF document text
    • https://vexakoloninabi.weebly.com/uploads/1/3/4/8/134851928/kukolerafokigu.pdfIn PDF document text
    • https://mivifasev.weebly.com/uploads/1/3/1/4/131483453/xasif-navepitoxo.pdfIn PDF document text
    • http://wudenufodoroziv.scienceontheweb.net/list_of_important_days_in.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/d62d4f50-9076-4ade-8e97-e80d359a0ba3/what_is_the_story_of_the_lady_of_the_lake.pdfIn PDF document text
    • http://ruvuvekato.epizy.com/exercises_for_grade_2_ac_joint_separation.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9494514a-910c-4116-b7bc-05784caccd31/the_adventures_of_augie_march_quotes.pdfIn PDF document text
    • http://wutejaxevewef.myartsonline.com/selenium_java_tutorial_youtube.pdfIn PDF document text
    • https://3d73ec66-e24e-4607-99a5-aa3c333c10ea.filesusr.com/ugd/a96454_cc48558801c041fc814995997edd6fd0.pdf?index=trueIn PDF document text
    • https://9fbeb193-358d-48fe-b9d9-45f8b63f6b3c.filesusr.com/ugd/ab67b9_baf959c13dba45fd99c3c46456d3d460.pdf?index=trueIn PDF document text
    • https://3c1efe6f-6e34-41bb-a2c4-2be85dd3cb33.filesusr.com/ugd/41f880_41e45a32899c4e8db7b4186089fbc0d5.pdf?index=trueIn PDF document text
    • https://d5e9a058-cbdc-4968-ba72-30cdbf1e36a3.filesusr.com/ugd/9cfd0a_0391a9d034c34b4a954c151fd14a2e4b.pdf?index=trueIn PDF document text
    • http://sosekemuzunenu.rf.gd/antiarritmicos_farmacos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/997adcde-30c8-45f8-ad92-6d6d47fc7f13/what_books_to_read_if_you_like_game_of_thrones.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_off00018ce0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18CE0 5368 bytes
SHA-256: 8304928d9b138c26076644127ddabc41ab9b16c22ae553c911edb45a06af08b8
font_01_sfnt_off00019f3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19F3A 11528 bytes
SHA-256: 632e5a0138b811ea501f693d2746e6282e9195a453735dd7f4e6a81ad659d322
font_02_sfnt_off0001c692.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C692 16204 bytes
SHA-256: 541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501