Malicious PDF — malware analysis report

Static analysis result for SHA-256 341166a43f1c0512…

MALICIOUS

PDF

70.3 KB Created: 2021-03-31 05:14:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 3505fe170f039e7d73ed5c5bcab1c06d SHA-1: 2af418840aa6d0cd0710a99d52d23942cdfd9089 SHA-256: 341166a43f1c0512762875074005016b774818d275642cf04ab3d9aacf67297e
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URIs, with one notable example being https://zajinet.ru/wix?keyword=fe+chemical+practice+problems+pdf. The presence of many links, some on disposable hosting, suggests an attempt to manipulate search engine results or distribute malicious content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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.
  • 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://zajinet.ru/wix?keyword=fe+chemical+practice+problems+pdf PDF link annotation
    • https://cdn.sqhk.co/getabemuto/oJGgeji/carx_drift_racing_mod_apk_1._10._1.pdfIn PDF document text
    • https://cdn.sqhk.co/zubafena/pglyubd/missguided_camel_longline_coat.pdfIn PDF document text
    • https://cdn.sqhk.co/tajudozizif/Njcgjmq/manchester_smash_my_hero_academia.pdfIn PDF document text
    • https://cdn.sqhk.co/tokafumotebi/3Csgggd/starlink_battle_for_atlas_xbox_one_price.pdfIn PDF document text
    • https://cdn.sqhk.co/zamepeja/KqXihgf/9047563922.pdfIn PDF document text
    • https://cdn.sqhk.co/valipovu/gYmjijZ/kadebavej.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c488ef8d-5c31-4f3a-8823-18670fe74292/great_coach_quotes_football.pdfIn PDF document text
    • https://s3.amazonaws.com/wefemabeni/fist_fight_2017_parents_guide.pdfIn PDF document text
    • https://aa6eca1a-c690-4a36-985e-a873157a80b3.filesusr.com/ugd/081493_3342ffd8c30549fca661174b8451eeae.pdf?index=trueIn PDF document text
    • https://2ac56fc1-f7ee-4366-9cb2-1681469c68ee.filesusr.com/ugd/b914b5_fbd17ed1b65646979fedd1b580f68554.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c64bf299-8e29-416c-b33e-20eaac83e87e/ms_drivers_license_phone_number.pdfIn PDF document text
    • https://a7ed8af5-5e4a-4eaf-98d7-51655494ca15.filesusr.com/ugd/b5c45a_f092986d93a94a11aedbb8aac4f93fc2.pdf?index=trueIn PDF document text
    • https://627f215e-41ba-4aa4-9906-5f9f9d117739.filesusr.com/ugd/8ab72e_909ffc44196246b981252084794d1136.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bifadiwuwileji/dell_760_sff_specs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d1bb68b-6921-4c6d-a07d-635f3097e918/how_do_i_get_windows_10_for_free_in_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/289bc50a-1e6e-4c56-8d27-e964fb3f2a30/how_often_should_i_service_my_jet_ski.pdfIn PDF document text
    • https://c538924d-9290-4e35-808b-5013ecaac822.filesusr.com/ugd/047ea9_49d8b0071e464cb0bdf61a928f2a905e.pdf?index=trueIn PDF document text
    • https://f1ddcea9-c323-452c-a4d3-aaefec61e50a.filesusr.com/ugd/defd8a_0e48bde734c04683ae39dc14afc02643.pdf?index=trueIn PDF document text
    • https://6f672a44-e16c-4921-a0f1-e3781c0647c5.filesusr.com/ugd/bda22a_851bc035f91945508454231fa2a847eb.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/018fe560-458e-4a19-96e7-20e2c2c4ba55/how_to_configure_dd-wrt_router_as_a_repeater.pdfIn PDF document text
    • https://s3.amazonaws.com/remeranexe/concave_and_convex_lens.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_off0000d1d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D2 5488 bytes
SHA-256: 435c9286f2bf9b9e530daf5e9e9db5ceef5b8a1291c79353d404cbc6fad90a83
font_01_sfnt_off0000e445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE445 11172 bytes
SHA-256: ef65416f2f7967d008d4c52eaaa3c9bd49a46eda707b71aac290f9a4d2b99353