Malicious PDF — malware analysis report

Static analysis result for SHA-256 c42e58fef2ea40c1…

MALICIOUS

PDF

74.5 KB Created: 2021-04-05 17:59:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 0c3f8c08b3274d00c4d8ba1f74a61ec7 SHA-1: 1ee9119b102aeaa3e6a6ee74be74509a8eae07be SHA-256: c42e58fef2ea40c1fafb3f56c637d512268d7d2a907262329368b5df943e098d
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded links pointing to external PDF files, many of which are hosted on disposable domains or known malicious redirectors. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute further malicious payloads. The ClamAV detection and ML classifier further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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.
  • 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://crophysi.ru/award?keyword=english+test+present+simple+pdf In PDF document text
    • https://tabogivazosepa.weebly.com/uploads/1/3/1/8/131871767/1dae32a102794.pdfIn PDF document text
    • http://xubegureluju.22web.org/zetinemusisez.pdfIn PDF document text
    • https://tofudilasikota.weebly.com/uploads/1/3/0/9/130969343/2011036.pdfIn PDF document text
    • http://xosijitede.22web.org/39546421651.pdfIn PDF document text
    • https://vilofezilo.weebly.com/uploads/1/3/0/7/130740065/6f480.pdfIn PDF document text
    • https://sugodaxekot.weebly.com/uploads/1/3/1/8/131872070/9168473.pdfIn PDF document text
    • https://rufawakifored.weebly.com/uploads/1/3/1/8/131856207/3714905.pdfIn PDF document text
    • https://lurevovikofa.weebly.com/uploads/1/3/4/6/134693735/f21c6465a4354e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wigelasipop.rf.gd/avengers_theme_sheet_music.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7d80432-35a1-47d6-ad5f-840815880c86/86223531030.pdfIn PDF document text
    • http://duxidomotafuzag.rf.gd/model_place_value_relationships_lesson_1.1_reteach.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d309ca70-7393-41b9-8227-9d0970efba3d/is_there_a_need_for_real_estate_appraisers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e87bbc0-8e8e-4c3d-abdb-245aeb69d222/what_is_the_best_traeger_to_get.pdfIn PDF document text
    • https://7f2467c6-0d80-4e38-8df7-27624e0b9669.filesusr.com/ugd/e19533_19a22f8fe2324d6fb6313de739659f2b.pdf?index=trueIn PDF document text
    • https://9abff256-b119-4e75-a612-dfc075f5428e.filesusr.com/ugd/c73517_030037fcfafa44798711361a5047356a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f1945c3-0852-4f2d-889c-f4fbbaba07f3/23503673721.pdfIn PDF document text
    • https://78f121e6-5824-477f-9480-4bf23eba804c.filesusr.com/ugd/9564ad_e35ff3be53ed4a9abe720c23edd7bb72.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/83f487cd-c467-4b17-9dac-7b1a0cecf1b1/tres_metros_sobre_el_cielo_full_movie_subtitrat_in_romana.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_off0000e6f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F1 5200 bytes
SHA-256: 20366c781b60c60c60a0bf86cd77b6f99d75f6894c4a19a28d68f998bd91784f
font_01_sfnt_off0000f880.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF880 10716 bytes
SHA-256: 0be0223d87b10844c2cd87c96467376240b4a68268f74a3d054ea6d53a16d748