Malicious PDF — malware analysis report

Static analysis result for SHA-256 4efb0bf077a79e75…

MALICIOUS

PDF

81.5 KB Created: 2021-05-24 04:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 912d33538f2ed16c4302b41e738bfe20 SHA-1: 5e96511fc24b235bb5ff632ea3dcfa18bd59daa8 SHA-256: 4efb0bf077a79e759fc1d32c5881e8ac414576af125a48462dd528897d273e6d
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 0.9993

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://ponafet.ru/strik?utm_term=introduction+to+neurogenic+communication+disorders+brookshire+pdf PDF link annotation
    • https://rasisepuwefu.weebly.com/uploads/1/3/4/6/134678142/c52e9ba7e22d8.pdfIn PDF document text
    • https://zapidowezagija.weebly.com/uploads/1/3/4/0/134041255/63749eb7b5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420248/normal_603bdcfc8c38c.pdfIn PDF document text
    • https://vimosetadasosus.weebly.com/uploads/1/3/2/7/132740377/ragil_revudigul_zajedaj.pdfIn PDF document text
    • https://kapukafasid.weebly.com/uploads/1/3/1/4/131437878/9994921.pdfIn PDF document text
    • https://benesigonej.weebly.com/uploads/1/3/1/6/131607635/xiwaviza.pdfIn PDF document text
    • https://jeburetuzof.weebly.com/uploads/1/3/4/3/134306955/newavugowexufif.pdfIn PDF document text
    • https://sifufunozomelu.weebly.com/uploads/1/3/4/7/134764248/nagigebirorififisag.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500887/normal_604d09d1f1410.pdfIn PDF document text
    • https://mofumamivuzav.weebly.com/uploads/1/3/1/0/131070192/9450820.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405642/normal_5ff94331affdb.pdfIn PDF document text
    • https://vasaradafivoza.weebly.com/uploads/1/3/6/0/136048391/tagugoxevadetizapiso.pdfIn PDF document text
    • https://toraboretopupu.weebly.com/uploads/1/3/4/7/134769369/nedotadanula.pdfIn PDF document text
    • https://zovodexipelozas.weebly.com/uploads/1/3/4/4/134401167/7833754.pdfIn PDF document text
    • https://jepololazatozuj.weebly.com/uploads/1/3/4/6/134601538/winajobelazedujo.pdfIn PDF document text
    • https://xizejaselaz.weebly.com/uploads/1/3/4/3/134357450/7949893.pdfIn PDF document text
    • https://buzotifosu.weebly.com/uploads/1/3/2/6/132695554/4374433.pdfIn PDF document text
    • https://lobogisotu.weebly.com/uploads/1/3/4/8/134870795/misotoroxa.pdfIn PDF document text
    • https://bozuwosumexoxal.weebly.com/uploads/1/3/2/6/132682772/nuwexoxupuxano.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381738/normal_60192c855abc6.pdfIn PDF document text
    • https://sepefawepuvikex.weebly.com/uploads/1/3/5/3/135384525/tijutebe.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/seriposuj/lazetowogisavexatiferabeg.pdfIn PDF document text
    • https://s3.amazonaws.com/dumupa/68026509150.pdfIn PDF document text
    • https://s3.amazonaws.com/zuxime/ryobi_battery_charger_red_light_blinking.pdfIn PDF document text
    • https://s3.amazonaws.com/regufojalojaza/how_long_do_hearing_aid_batteries_last.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_off0000fc55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC55 5680 bytes
SHA-256: c4f0c7a5af61cbe0b5bc0fff922be0f1fa0c1e96c400c91559b701ab957db240
font_01_sfnt_off00010f77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F77 12412 bytes
SHA-256: c3e13881a09536b2beaffa653acd850e44aff7d579ffc0bee22883150f0676bf