Malicious PDF — malware analysis report

Static analysis result for SHA-256 44b923f1a9d82d6f…

MALICIOUS

PDF

76.7 KB Created: 2021-05-21 21:47:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: b81d51b67572158a207a96f667f68b27 SHA-1: 08027c8775e79a2ae38b101c90c93eaaa27a1d20 SHA-256: 44b923f1a9d82d6f6fbf14cf5b5fbf50b98f4373e341728142362ac5891da30e
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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://jumiwimov.ru/strik?utm_term=can+you+mod+skyrim+on+xbox+one PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4389394/normal_604a39ea63d2b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476122/normal_6002d2f7a0376.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421624/normal_605bc862c4ddf.pdfIn PDF document text
    • https://pagafamowadaf.weebly.com/uploads/1/3/4/8/134878907/f1124b98.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393626/normal_603295ce8e968.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418781/normal_5ffd418d642e4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469135/normal_601bab7aabdbb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374207/normal_5fd7b77fc2d16.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457862/normal_603b828eca138.pdfIn PDF document text
    • https://mavitebe.weebly.com/uploads/1/3/1/1/131163983/326300.pdfIn PDF document text
    • https://powumebaporisav.weebly.com/uploads/1/3/4/8/134891471/tolesaro.pdfIn PDF document text
    • https://jenafowumavadas.weebly.com/uploads/1/3/1/4/131437472/fidigepoka.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411691/normal_5fe27e3aee418.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485149/normal_6019075a750f6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368222/normal_5fcb0201a5ae7.pdfIn PDF document text
    • https://lipixifafamuxa.weebly.com/uploads/1/3/0/9/130969384/kudaniri.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wewiro/vafoduduzodut.pdfIn PDF document text
    • https://s3.amazonaws.com/viboxikuz/algebra_word_problems_worksheet_grade_8.pdfIn PDF document text
    • https://s3.amazonaws.com/zatazewoz/best_android_phone_under_5000_rupees.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6001dfb0-5292-4772-a527-8698d4abcc64/ron_paulk_workbench_2_plans.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d011af28-5e1c-4ee3-b0ce-e67649bdba5a/duwogipoteroxuxuvi.pdfIn PDF document text
    • https://s3.amazonaws.com/mokixetat/80054048646.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa5267f5-b1ac-4da2-99a4-2b27247bccff/xotimepivesepa.pdfIn PDF document text
    • https://s3.amazonaws.com/makixibawumebol/tokanigekiw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de97268f-24c7-4521-8394-cfa26a81e63a/cuantos_tipos_de_derechos_fundamentales_existen.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_off0000ef30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF30 5220 bytes
SHA-256: a84a225520f06c5fa40024db312ab964b4763e45df7f24ce0aac7061fef7c0c2
font_01_sfnt_off000100df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100DF 10576 bytes
SHA-256: 04886bb35ee83145cbb84040fe4bc71c904b991effc4f131129cc829decca8b8