Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf760ec3b8448924…

MALICIOUS

PDF

71.4 KB Created: 2021-05-17 12:35:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: f69473844405d80a017277f3cf50de0e SHA-1: 236a6b26701c6f07aa7d5b11a22adb7a64a91ffb SHA-256: bf760ec3b84489240c9b285edd379ad001a57afc0188a784f62398264d739735
186 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm and by ClamAV as Pdf.Phishing.Trojan. It contains numerous external URLs, with one prominent URL being https://jumiwimov.ru/strik. The presence of a link farm suggests an attempt to distribute malicious content or phish for credentials by overwhelming the user with choices. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://jumiwimov.ru/strik?utm_term=college+physics+knight+4th+edition PDF link annotation
    • http://giftcard-sale.store/jowibusuwadomisaluviwesaw56wx.pdfIn PDF document text
    • https://cdn.sqhk.co/zojoguxuban/xYtygid/top_10_list_makers_crossword.pdfIn PDF document text
    • https://cdn.sqhk.co/guwezasov/ezjjhcP/splashy_cats_endless_zigzag_web.pdfIn PDF document text
    • https://virutabadipepuv.weebly.com/uploads/1/3/1/3/131398083/b9ec0b40e80f9.pdfIn PDF document text
    • http://azalea.store/university_of_miami_bookstore_coral_gables_flq3dsp.pdfIn PDF document text
    • http://nosinoski.shop/sofewumezagadelipijugs08g.pdfIn PDF document text
    • https://cdn.sqhk.co/potiribuwuf/UEgehdy/92099920734.pdfIn PDF document text
    • http://nesobaka3.xyz/target_grants_for_field_tripsee41x.pdfIn PDF document text
    • https://talipugetajizan.weebly.com/uploads/1/3/4/8/134862074/2753270.pdfIn PDF document text
    • https://cdn.sqhk.co/zejizoguzut/7Mwhhig/81550541094.pdfIn PDF document text
    • https://cdn.sqhk.co/rekutadis/gd8jjhh/19729506316.pdfIn PDF document text
    • https://cdn.sqhk.co/muzexeragod/h0jbbgh/2788499248.pdfIn PDF document text
    • https://cdn.sqhk.co/lawafopugu/sWljeja/pet_doctor_rockwall_hours.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://22e44a25-5b44-49ab-8bd1-9de78d2943b2.filesusr.com/ugd/cce535_b7fa6079c8ff4f1db7a5d403829f51da.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c8e297a8-ea5a-47c3-8990-7a9a6f80bd7f/98755338051.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b636d16-da24-476c-b825-08f3e21ca2aa/how_to_connect_bluetooth_to_pioneer_mvh-s21bt.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/91074d12-1e6f-4439-a2d5-8ea15677e9fb/43766793405.pdfIn PDF document text
    • https://1f2f8e77-98df-4c5e-b88a-83bc2b612b58.filesusr.com/ugd/5c7528_1d07b46ca21d48aa955962bd4ac3fe92.pdf?index=trueIn PDF document text
    • https://e1ca4115-fb55-43f9-84f1-eaf814f8c83f.filesusr.com/ugd/18122d_63233c6849324c339e2afdce5cf87833.pdf?index=trueIn PDF document text
    • https://3cd6846c-369c-4875-9c63-132df726a2dd.filesusr.com/ugd/7ab50f_02c25fba6558410b8e827c9adf02ed9e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0baf2566-156a-4766-9379-9c412e53f7aa/vefodurubakemedalijidavaf.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_off0000da71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA71 5188 bytes
SHA-256: ff9ab7312c827abaa6fcc69bdb6352fc22868827be6961b1532dae4c5d1ec652
font_01_sfnt_off0000ec2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2B 10768 bytes
SHA-256: 6a3ff2a961eed8a37c42ec76518edcfee3c4421f6b932e0253a7052d2e6436fd