Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b23df71672d08eb…

MALICIOUS

PDF

85.0 KB Created: 2021-03-12 01:28:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 5f25a79a0866aaea965dda025471a7d6 SHA-1: 9a3ab6a5099de5aadbbe750043bfea5ac14b74f7 SHA-256: 3b23df71672d08eb141f6de7a73795bf60114afbd1bff0e3b93056cbe76c65a2
194 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an invoice-themed lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://fokemale.ru/123?utm_term=java+jdk+8++ubuntu PDF link annotation
    • https://cdn.sqhk.co/parikozug/UQifqse/mastercrafters_clock_and_radio_company.pdfIn PDF document text
    • http://xatakafigudu.getenjoyment.net/lyrics_five_nights_at_freddys_2_song_-_the_living_tombstone.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473954/normal_6035a0c0434c5.pdfIn PDF document text
    • https://cdn.sqhk.co/mujejadalale/eifthep/retro_kong_classics.pdfIn PDF document text
    • https://cdn.sqhk.co/vupapevixu/jiS2hin/lip_art_3d_satisfying_lipstick_tattoo_art_games.pdfIn PDF document text
    • https://cdn.sqhk.co/kigimijexap/OhiXifs/ashraf_udas_song.pdfIn PDF document text
    • http://mebovedu.getenjoyment.net/banking_regulation_act_1949_notes.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450719/normal_60029c401d5e6.pdfIn PDF document text
    • https://sefizofemaj.weebly.com/uploads/1/3/4/2/134266575/c2575064c.pdfIn PDF document text
    • http://mobufuwiwid.medianewsonline.com/63208124347.pdfIn PDF document text
    • http://kunepuvobimamin.medianewsonline.com/96795936146.pdfIn PDF document text
    • https://fizubuvi.weebly.com/uploads/1/3/5/3/135301632/rebixovugoj_buniti_zejufivosowajow_xobatasod.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393635/normal_5fcdc3ffbaab3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476268/normal_600fe791a0fea.pdfIn PDF document text
    • https://febadezupuwile.weebly.com/uploads/1/3/1/0/131071278/xibag.pdfIn PDF document text
    • https://cdn.sqhk.co/keximovib/chaLxha/free_full_hollywood_movies_download_sites.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://megalikivokilir.rf.gd/vizofamavi.pdfIn PDF document text
    • http://bapinusajix.rf.gd/gesijakoforerulevo.pdfIn PDF document text
    • http://lexekuduwowig.atwebpages.com/karl_marx_communist_manifesto_malayalam.pdfIn PDF document text
    • http://leruxesotagas.rf.gd/charlotte_russe_size_guide.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00011b8a.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11B8A 23216 bytes
SHA-256: f286c385d0bf892b89ccba7dd959e252d7706bf63447a5658d8f03ecb98f7a97
font_00_sfnt_off0000e539.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE539 5036 bytes
SHA-256: e3df100dd7f9e33e4d8b4db8af58f60efd19b32bc0310ad3297dab76b4383386
font_01_sfnt_off0000f67e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF67E 10968 bytes
SHA-256: 78237ac16f0cd51f5aa64b6da49eb37ede64bf742ad2630be0bb62eeb1c7d4e8