Malicious PDF — malware analysis report

Static analysis result for SHA-256 916408b6baa17490…

MALICIOUS

PDF

77.0 KB Created: 2021-01-27 01:53:02 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: c7857c0c090c00965f5dd2d23e156d89 SHA-1: d42e07570d38ab9990b74f665e501b2250f5875d SHA-256: 916408b6baa17490e7013d5286ea077822ed08c96d1a4d9df87f6a1d6fa35584
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or redirector services, indicating a link farm designed to distribute traffic. One critical heuristic identified links to known malicious redirector infrastructure, and ClamAV detected it as Pdf.Phishing.Trojan. The ML classifier also strongly indicated maliciousness. The document body is heavily obfuscated and appears to be junk data, suggesting the primary function is to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • 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://crophysi.ru/123?utm_term=kalua+pork+and+cabbage+oven+recipe In PDF document text
    • https://xakirajurupani.weebly.com/uploads/1/3/2/3/132303083/4828265.pdfIn PDF document text
    • http://nemurirewokow.iblogger.org/boss_bengali_full_movie_hd.pdfIn PDF document text
    • https://cdn.sqhk.co/vagizabibo/ibX3zjh/datijojiboposefom.pdfIn PDF document text
    • http://pimebujeben.66ghz.com/sokalonudexim.pdfIn PDF document text
    • https://cdn.sqhk.co/wogokodu/gdxfjgX/electronic_music_festivals_europe.pdfIn PDF document text
    • https://cdn.sqhk.co/jikikavadaja/wQhdhaQ/meter_reading_jobs_south_east_london.pdfIn PDF document text
    • https://cdn.sqhk.co/wakivugex/Rjbhgge/zombie_invasion_wow_ptr.pdfIn PDF document text
    • https://cdn.sqhk.co/jajotulix/jdfjdgj/81898912582.pdfIn PDF document text
    • https://cdn.sqhk.co/jemajujo/hihdjhZ/simcity_buildit_cheats_iphone_no_survey.pdfIn PDF document text
    • https://xoselupovogim.weebly.com/uploads/1/3/4/6/134610719/relaretokobok_dijukuduwuki_vorokilujubefub.pdfIn PDF document text
    • https://cdn.sqhk.co/diwiporeb/gjiijxt/jaxugogumulijumapekuneg.pdfIn PDF document text
    • https://xazonidunigi.weebly.com/uploads/1/3/4/5/134590253/tedidisomukeka.pdfIn PDF document text
    • http://faxizila.iblogger.org/c_format_string_right_align.pdfIn PDF document text
    • https://rejasujewefem.weebly.com/uploads/1/3/0/7/130738882/dezapozi.pdfIn PDF document text
    • https://cdn.sqhk.co/wevafofed/jbjbwjc/92531190624.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nenimon.epizy.com/bang_bang_movie_english_subtitles.pdfIn PDF document text
    • http://gorevifero.epizy.com/80770149378.pdfIn PDF document text
    • http://roniwixanedif.epizy.com/boxamosilazixelenomolubem.pdfIn PDF document text
    • http://nazonuretowu.epizy.com/jenop.pdfIn PDF document text
    • http://rubuvajaroxe.epizy.com/baby_photos_hd_wallpaper.pdfIn PDF document text
    • http://lafatakijuton.epizy.com/soxatu.pdfIn PDF document text
    • http://wufajin.rf.gd/vivone.pdfIn PDF document text
    • http://kodireso.epizy.com/panepopepudakenutasoduxa.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_off0000ef73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF73 5296 bytes
SHA-256: d92d1e9e475b37f160fbfd3b828123b2c6b1ff410602cc116cae154309002d92
font_01_sfnt_off0001018a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1018A 10756 bytes
SHA-256: 5037bc35fffd3638fe1badfb9a0587f6eb7f3934ae937d92ce7d7b661cffc022