Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd6d0b761c891e31…

MALICIOUS

PDF

76.3 KB Created: 2021-04-04 06:30:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 3710d73b7ac7ebc8e6d3dab69198d857 SHA-1: 1f1b112f647d9486c670305772f1c005ad00493a SHA-256: cd6d0b761c891e318da959ba2b074887ebe28215f3f68283566a0fa7d73e92b2
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly suggests maliciousness. The embedded URLs are likely intended to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://nipisod.ru/award?keyword=educational+administration+and+supervision+books+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4407795/normal_6007a3c639e9c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380072/normal_5fe38b14c1b3e.pdfIn PDF document text
    • https://dowisapi.weebly.com/uploads/1/3/4/2/134266119/1667319.pdfIn PDF document text
    • https://zetitazafoxiz.weebly.com/uploads/1/3/4/0/134040412/54dd3b81e.pdfIn PDF document text
    • https://xewaxegixu.weebly.com/uploads/1/3/0/7/130739020/logefimowofapu.pdfIn PDF document text
    • https://zunepijubu.weebly.com/uploads/1/3/3/9/133986973/e1a1d.pdfIn PDF document text
    • https://dajexuxeguse.weebly.com/uploads/1/3/4/8/134859846/2223803.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481417/normal_5ffcce37b3c4e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463263/normal_603cb7a0e40a7.pdfIn PDF document text
    • https://jowatewiko.weebly.com/uploads/1/3/1/3/131380225/tunibofifux-kuxuvamunes-jeriji-vezuxoponupidef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451950/normal_6012b0843aa3d.pdfIn PDF document text
    • https://tuwunofibe.weebly.com/uploads/1/3/4/6/134657164/3f3a7a5655.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://filamejukak.epizy.com/kolijigagev.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6583c7b-67fc-4221-bff4-6b3fd00e997f/adobe_premiere_pro_cc_2018_free_trial_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/903c459e-13a2-45ec-bf33-e752265cb9dd/zefipabolufipomilon.pdfIn PDF document text
    • https://0dd4521b-3e41-4083-9bcc-807cce03ae78.filesusr.com/ugd/cfe2e9_851a72030f6e41f9aa54eb7894557ff7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d58e5413-44ec-4529-96d3-66283b4a4fcc/speed_queen_washer_and_gas_dryer_reviews.pdfIn PDF document text
    • http://waduxixefe.rf.gd/hasil_bahtsul_masail.pdfIn PDF document text
    • https://9005a25f-7293-4a73-bb0f-bc58e8c16807.filesusr.com/ugd/e3834b_c7dcc6dcb3404cd7be94f7bb57571f5c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/028a3594-573e-4de5-b985-8494f32179bc/25138374428.pdfIn PDF document text
    • http://fimamuvumurepu.rf.gd/46300261371.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD51 5404 bytes
SHA-256: 8fcf64315ccad730b6a67e3ac3a20f2f1598fcc95e0bb3cd6c40c0ad89b19b78
font_01_sfnt_off0000ef96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF96 11064 bytes
SHA-256: e5dc32cffe9e0213eeb4a5912a1d806f4c26aa46c040a24f0cd32a998bd2fffc
font_02_sfnt_off0001155e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1155E 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3