Malicious PDF — malware analysis report

Static analysis result for SHA-256 c52e791ee1b1eb48…

MALICIOUS

PDF

43.7 KB Created: 2020-10-02 22:14:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: f04833ef353888ca1e84c84da2c716f6 SHA-1: b0f344690af063fc387e36abb374c5c1c0371a6e SHA-256: c52e791ee1b1eb484bfc0fee47f96cd4f09c5339e370ce87fd69c673e7729139
194 Risk Score

Malware Insights

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

The PDF contains numerous links to external PDF files, many of which are algorithmically generated and point to potentially malicious domains. One critical heuristic identified a link to known malicious redirector infrastructure at https://cctraff.ru/strik?keyword=vte+prophylaxis+guidelines+2020+pdf. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains some of these URLs, suggesting an intent to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://cctraff.ru/strik?keyword=vte+prophylaxis+guidelines+2020+pdf In PDF document text
    • http://files.koreanamericanhealthconference.com/uploads/1/3/2/6/132695915/lomuginepil_tebiropamevub_bomakikimarune.pdfIn PDF document text
    • http://files.tasteofpariscarryout.com/uploads/1/3/0/7/130775918/2067394b.pdfIn PDF document text
    • http://files.ww-wares.com/uploads/1/3/0/7/130776644/zomuvelisidevuj-pewinudot.pdfIn PDF document text
    • http://xokavoba.brookwoodtrackclub.com/uploads/1/3/0/7/130776795/poxadiwetesizajarizi.pdfIn PDF document text
    • http://jonezibo.leatippett.com/uploads/1/3/0/8/130814017/guraka_fufuv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0483/2955/6131/files/2528137461.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0483/5599/9897/files/wages_for_housework_poster.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0492/2756/3164/files/tar_heels_basketball_schedule_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ecac93d-03f9-4895-9bb1-cb723a25b47f/94235311228.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dab20519-0e45-4ad4-b0e3-c0fa94f95a3f/20449291972.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0477/5415/0044/files/38030102975.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0484/7298/1658/files/black_sports_and_entertainment_hall_of_fame_martin_short.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0483/8889/8973/files/97342095389.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_off00006c1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6C1E 5712 bytes
SHA-256: 7ec2b8d9bcc15b90e201659bcb3f341e5fb4e8d1aa5da85975e2252c97503ed2
font_01_sfnt_off00007fa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7FA2 10088 bytes
SHA-256: 39b7d531ddf32985dda6e3ca91903435e2a7f2c5f6fed00030272e82c7a4c2ab

Open this report in the interactive analyzer, or submit your own file for analysis.