Malicious PDF — malware analysis report

Static analysis result for SHA-256 16c0ae7d1a85fba7…

MALICIOUS

PDF

72.5 KB Created: 2021-05-19 22:28:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: abb925fdbecf0000fa4ccde038813c4a SHA-1: c26647b342961c671e757dbc1925da98df65466a SHA-256: 16c0ae7d1a85fba7146ba239cafae9c22b4834d38ef26ea5c6acda9c6026ec19
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, a technique often used for SEO spam or to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent. The embedded URL 'https://druttle.ru/strik?utm_term=what+is+manual+transmission+fluid+type+a' suggests a phishing or spam lure, disguised as a search result.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://druttle.ru/strik?utm_term=what+is+manual+transmission+fluid+type+a
    • https://cdn-cms.f-static.net/uploads/4446931/normal_60492d652ac0e.pdf
    • https://zitujizu.weebly.com/uploads/1/3/4/7/134731650/kovevawoj.pdf
    • https://dekamukovesu.weebly.com/uploads/1/3/5/3/135324216/taketegifudojawesano.pdf
    • https://cdn-cms.f-static.net/uploads/4404984/normal_603b7db6b8724.pdf
    • https://xogiwudib.weebly.com/uploads/1/3/4/7/134715522/2284402.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/c0a740b2-1632-4bd4-8a7f-92fb278a9d04/vokifebajonizedoxajosewu.pdf
    • https://uploads.strikinglycdn.com/files/ba0770a5-df61-47fc-84a7-5d6b0cb01c30/fender_hot_rod_deluxe_30_watt.pdf
    • https://uploads.strikinglycdn.com/files/62e456b1-c935-4634-8c83-61859c70f816/how_to_increase_your_mental_fortitude.pdf
    • https://uploads.strikinglycdn.com/files/0a9bba35-f7a5-4dac-a81f-f3254abea1c1/70506588003.pdf
    • https://uploads.strikinglycdn.com/files/1b721a67-a493-4679-b84a-a9dbf746d4dc/nixafax.pdf
    • https://uploads.strikinglycdn.com/files/11886a4e-7716-4c11-837c-87b23df67f87/68276650947.pdf
    • https://s3.amazonaws.com/tenunud/15820841166.pdf
    • https://uploads.strikinglycdn.com/files/279f0b30-ee47-40ff-b687-47599becada0/kosajigusosim.pdf
    • https://uploads.strikinglycdn.com/files/d689722d-18d5-4bb7-8a9f-de6a4d8bfb27/what_kind_of_jobs_can_you_get_with_a_bsba_degree.pdf
    • https://uploads.strikinglycdn.com/files/f58f128c-562c-4e5e-8edc-1f997189b726/zexuzupajozokegazemikuju.pdf
    • https://uploads.strikinglycdn.com/files/7947d498-ced3-4f7c-986f-e4ba5c0dd275/1669749677.pdf
    • https://s3.amazonaws.com/wutogugej/what_is_the_main_idea_of_casey_at_the_bat.pdf
    • https://uploads.strikinglycdn.com/files/aada302d-f4d7-45a5-84d1-d1107ddd4a57/7_day_mind_diet.pdf
    • https://s3.amazonaws.com/sixolose/interpreting_p_l_financial_reports.pdf
    • https://uploads.strikinglycdn.com/files/698618fc-0e46-4778-81ce-1ba08245b1a0/68267918842.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_off0000de4f.bin
5e3d6ce86093bc05b1f3f9a4b4859d908f631fc5dfff31fed5d2f2048bb22c75
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4F 5396 bytes
font_01_sfnt_off0000f091.bin
fd7441fbd70a2de610e3ce6beb8a72347695131d65a81de6883cf85e4db10ae5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF091 10652 bytes