Malicious PDF — malware analysis report

Static analysis result for SHA-256 21e1a93bbfbd98b4…

MALICIOUS

PDF

86.7 KB Created: 2021-03-19 01:40:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: b37a4f35430d35d24d22fd59019d8e5a SHA-1: 99c5bbd2020cdb7d4bbf51124894033c9962a6e8 SHA-256: 21e1a93bbfbd98b4965f8e39d5c8bf8fca7ce419021867e14fe647722ca9b203
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to disposable hosting and employing UTM parameters, indicating a link farm designed to redirect users to malicious sites. The document body, though heavily obfuscated, appears to contain text related to the juvenile justice system, likely a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://golowaki.ru/strik?utm_term=what+is+the+main+purpose+of+the+juvenile+justice+system PDF link annotation
    • http://fastpeysistem.online/fut_draft_glitch06xnh.pdfIn PDF document text
    • http://jaxagogilexet.sportsontheweb.net/66126975750.pdfIn PDF document text
    • http://manaxupupili.iblogger.org/risd_academic_calendar.pdfIn PDF document text
    • http://fepaporipevari.mypressonline.com/71330412219.pdfIn PDF document text
    • http://xesabuzusoneb.66ghz.com/pitudipibudewinofujumaw.pdfIn PDF document text
    • http://sipamuxagiporen.iblogger.org/60277795167.pdfIn PDF document text
    • http://smcjd.com/gisazewexutetlo17.pdfIn PDF document text
    • http://linefofaxugedu.mywebcommunity.org/what_is_a_certified_law_student.pdfIn PDF document text
    • http://jiguvesowa.22web.org/sentry_safe_key_how_to_open.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/d0a57048-c939-4551-b48a-ba93fbb2246a/monthly_metrocard_nyc_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6a263d9-3d05-428b-98fb-30c64471a368/elements_of_nature_and_properties_of_soil_3rd_edition.pdfIn PDF document text
    • https://s3.amazonaws.com/telasebisu/subdomain_delegation_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/ragejufa/ti-30xa_solar_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/gawabog/70672488444.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ff353630-6d8d-4c3a-8d3a-07dc79072ce4/siwelefamoduvewerelo.pdfIn PDF document text
    • http://vemevusakeke.epizy.com/59380751582.pdfIn PDF document text
    • http://fubuwutunofo.rf.gd/45363497853.pdfIn PDF document text
    • http://lugimeviguv.myartsonline.com/lepebixazilud.pdfIn PDF document text
    • https://s3.amazonaws.com/matogapibelifiv/muscle_gain_workout_plan_at_home.pdfIn PDF document text
    • http://komopojanali.rf.gd/4799395821.pdfIn PDF document text
    • http://lasuwutiganije.rf.gd/57002767071.pdfIn PDF document text
    • http://nejesezape.myartsonline.com/d-link_dir-655b1_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/xojafemori/50770780769.pdfIn PDF document text
    • http://gemosufijubimup.epizy.com/chrono_trigger_corridors_of_time_sheet_music.pdfIn PDF document text
    • http://lotirejotan.rf.gd/76529522161.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3376cc70-dd6e-4822-b518-a559d91bb55b/ruud_achiever_water_heater_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/23836700-1cad-499e-a258-2f5c56f3254a/bijipofif.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000106e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E8 5388 bytes
SHA-256: 159650e955b6526e10bb5324de47841e3ca32ec01aee481a4ed94ad26d0b9470
font_01_sfnt_off00011928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11928 10532 bytes
SHA-256: 10b97c86f0d5aa98ec15cbf78acb01d41abaf7da09dc869a84b5622731cdfe86
font_02_sfnt_off00013ca7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CA7 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361