Malicious PDF — malware analysis report

Static analysis result for SHA-256 11237dd70812be86…

MALICIOUS

PDF

78.8 KB Created: 2021-02-24 00:55:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: d155fce83fb346d18b763a3a6fbc9b6f SHA-1: 7fd5174557baab2d92ed0fd93ee65b8b6f43eafd SHA-256: 11237dd70812be869baa5db1ae2c8f7eda7ab3e44fbd2d03a1faea325cc4b0e1
244 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on disposable domains and appear to be part of a link farm. One critical heuristic indicates a link to known malicious redirector infrastructure. The document body, though partially obfuscated, contains text related to an 'answer key', suggesting a lure to trick users into clicking these malicious links. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=2020+amc+10a+answer+key In PDF document text
    • https://nazisedisan.weebly.com/uploads/1/3/1/8/131871674/lexekeguguzesatejub.pdfIn PDF document text
    • http://50offstore.info/linux_systemd_cheat_sheets0azi.pdfIn PDF document text
    • http://creditreportus.info/neet_biology_syllabus_2018rlr5c.pdfIn PDF document text
    • http://study-english-05.site/91182933324sbjnt.pdfIn PDF document text
    • https://besuxape.weebly.com/uploads/1/3/4/3/134374749/4567e1.pdfIn PDF document text
    • https://wisetigu.weebly.com/uploads/1/3/4/3/134357320/minegutetunif.pdfIn PDF document text
    • http://masuvanoleseg.iblogger.org/cheran_express_platform_number_in_chennai.pdfIn PDF document text
    • http://zizopeja.22web.org/baby_girl_games_apk.pdfIn PDF document text
    • https://sujujawajiz.weebly.com/uploads/1/3/5/9/135964945/siketebuwojusok.pdfIn PDF document text
    • https://nokajavu.weebly.com/uploads/1/3/0/9/130969653/fe63a6e8.pdfIn PDF document text
    • https://xenesadu.weebly.com/uploads/1/3/0/7/130739949/rilomom_demesuxidu.pdfIn PDF document text
    • http://twobigs.space/1443694666uyha0.pdfIn PDF document text
    • https://wobereresexo.weebly.com/uploads/1/3/1/6/131606335/numiganab_kilebipapibemuk.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://veguvegonuz.rf.gd/do_royal_caribbean_beverage_packages_go_on_sale.pdfIn PDF document text
    • http://mibelajute.epizy.com/australia_time_date_format.pdfIn PDF document text
    • http://bawepefafaz.rf.gd/hsc_online_marksheet_maharashtra_board.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_off0000f591.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF591 5404 bytes
SHA-256: 562e2ea4a77af37dbe0419767e05d82996fdfd357ee413ac62cd0fc62b133bb0
font_01_sfnt_off000107f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F6 11208 bytes
SHA-256: 37e5c61c6841a9e01475792cd7f38cada32d83240e044f9cb03dce9e10a09fd4

Open this report in the interactive analyzer, or submit your own file for analysis.