Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a8c0bcd566c6694…

MALICIOUS

PDF

75.8 KB Created: 2021-05-28 06:18:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: a6a120adb366bcc3de9bb69c8f1f3cd2 SHA-1: 3e0b623ebb43d3ce75b8d98b0af885fa48de75f2 SHA-256: 0a8c0bcd566c6694bd2e9bf24ee899aaf131493ae758072945f94809faf68bbc
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these links. The embedded URLs and the nature of the link farm point towards an attempt to manipulate search engine results or lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://xajibur.ru/strik?utm_term=list+of+triangular+numbers+between+1+and+100 PDF link annotation
    • https://bunonosuvon.weebly.com/uploads/1/3/5/9/135976801/fogolatumasusixitud.pdfIn PDF document text
    • https://difidewuwigexej.weebly.com/uploads/1/3/4/6/134652805/zakuruborazerutuvida.pdfIn PDF document text
    • https://joripirido.weebly.com/uploads/1/3/0/7/130776040/buvojefadum.pdfIn PDF document text
    • https://wufezaju.weebly.com/uploads/1/3/0/7/130738917/sojebixunok_gedulupokixemer_butovitusaj.pdfIn PDF document text
    • https://fubolilodizewe.weebly.com/uploads/1/3/5/3/135312413/6800828.pdfIn PDF document text
    • https://zanelonovubut.weebly.com/uploads/1/3/4/3/134315015/7965023.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368468/normal_6052e3b29b58a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4479925/normal_5fe5ae2d608dc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379854/normal_6045e19a7fe1e.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/c57fe7d0-cbc7-4f30-9cff-9be896ece52f/neville_goddard_feeling_is_the_secret_deutsch.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/921abc6a-838f-4557-b98f-1be0a88ab151/jekofoxa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/242f3995-9902-4545-843c-ad804a2db515/78807135028.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81092441-30c6-4e10-aad7-5695695b7dd1/python_and_tkinter_programming_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50b11515-8d7c-460e-9c13-c17c7547f9de/important_dates_of_the_great_depression.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee7aa4b3-b172-4ef3-a280-c33049c1a1da/garmin_vivofit_3.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c24aae9a-7e07-4cf1-9e28-a7842b08190e/introduction_to_management_science.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7184b640-5d26-43f7-a71c-4362bf34e8cf/neelakasham_pachakadal_chuvanna_bhoomi_full_movie_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d0dc822-0c50-471f-a3d4-7ba5f2404f2b/rogiwuromavejuzukezikofip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a868873a-34ef-4141-964c-56a40644a064/hp_laserjet_1320_printer_firmware_download.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_off0000e611.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE611 5596 bytes
SHA-256: 6cdf8372ff1b9ac85b1b0f1a7b9536d2664d8a3a1a3c43ea96a9a3f8ecb52224
font_01_sfnt_off0000f91c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF91C 11868 bytes
SHA-256: 47b3b5f6d339b90fa71e6c04510c898132e96ac808295e5d77af400cea7880c5