Malicious PDF — malware analysis report

Static analysis result for SHA-256 a43f40fee988d2f3…

MALICIOUS

PDF

75.5 KB Created: 2021-04-07 14:40:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 99f0b40379a24374f821e583446a4f8b SHA-1: ce1992b949156ac4e3fc2da152a8ebfb79bba8c4 SHA-256: a43f40fee988d2f33aafbe007621802f9619ae407aef633d58d0d2a804abebd1
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, suggesting a link farm or redirection mechanism to malicious websites. The embedded URLs, such as 'https://midufefew.ru/123?utm_term=algorithms+in+cpp+pdf', are likely used to direct users to phishing or malware download pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://midufefew.ru/123?utm_term=algorithms+in+cpp+pdf
    • https://static.s123-cdn-static.com/uploads/4446398/normal_5ff38072c5444.pdf
    • https://cdn-cms.f-static.net/uploads/4402956/normal_5fd6197a50571.pdf
    • https://cdn.sqhk.co/giwegulatil/fnjiO01/mataxubofes.pdf
    • https://static.s123-cdn-static.com/uploads/4506131/normal_5fe278b126ff7.pdf
    • https://cdn-cms.f-static.net/uploads/4453102/normal_6036dc39a624b.pdf
    • https://cdn.sqhk.co/tirewaku/omheDaz/pirixulodajofojew.pdf
    • https://zavutotarewif.weebly.com/uploads/1/3/1/3/131379951/4216534.pdf
    • https://static.s123-cdn-static.com/uploads/4504554/normal_5fee3a6ec7427.pdf
    • https://cdn.sqhk.co/jeporikate/gadXdgi/video_call_chuck_e_cheese_s_live_online.pdf
    • https://nebomigefut.weebly.com/uploads/1/3/4/3/134359696/7721285.pdf
    • https://static.s123-cdn-static.com/uploads/4500446/normal_5fcce0d9d29f8.pdf
    • https://cdn-cms.f-static.net/uploads/4463034/normal_5fd173126633c.pdf
    • https://cdn.sqhk.co/vegedusovo/azOid0z/33729415151.pdf
    • https://cdn-cms.f-static.net/uploads/4447278/normal_603eecdd84cc4.pdf
    • https://cdn.sqhk.co/lokijuzim/fjdhijc/27104445427.pdf
    • https://cdn-cms.f-static.net/uploads/4465393/normal_5fd17f1d2539e.pdf
    • https://cdn-cms.f-static.net/uploads/4421623/normal_5fd7c3c30d267.pdf
    • https://cdn-cms.f-static.net/uploads/4505125/normal_606aa78122556.pdf
    • https://cdn-cms.f-static.net/uploads/4452385/normal_601ad1b0a83e7.pdf
    • https://cdn-cms.f-static.net/uploads/4502511/normal_6066b1992cd65.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/dc3ea0e6-33ab-4b6a-8017-eced5ce92042/37789793817.pdf
    • https://uploads.strikinglycdn.com/files/d7095ce8-ccff-49db-a22d-3ee76335ef06/72186391282.pdf
    • https://uploads.strikinglycdn.com/files/3020c5be-b9df-4d7d-9559-715ad1888a4d/introduccion_al_estudio_del_trabajo_oit_limusa.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e892.bin
67c3603cdd05186a6675856fef0ae1e03ec8c51a048ffa7f8d61ac1d0855e245
pdf-font-stream PDF embedded font (sfnt) at offset 0xE892 5348 bytes
font_01_sfnt_off0000faa5.bin
dabc362b43c13ca8034def4044765c911f0038a26b9dde7a0c8d1ad9f217297c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA5 11024 bytes