Malicious PDF — malware analysis report

Static analysis result for SHA-256 f39ff87630514896…

MALICIOUS

PDF

75.2 KB Created: 2021-06-01 14:11:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 31f6656057f993a54d2d0ae7250abd85 SHA-1: af3a9eb964d4090d034f0e7e4495d74cc337ceaa SHA-256: f39ff87630514896cbf0c699a3737fcfa0087953ebd7f51997042d83b4eed5ff
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as Pdf.Phishing.Trojan. The document functions as a link farm, containing numerous external URLs pointing to other PDF files hosted on disposable domains. This suggests an attempt to manipulate search engine results or to distribute further malicious content.

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://archism.ru/pbw?utm_term=what+is+the+shift+button+on+the+dstv+remote PDF link annotation
    • https://xebokedobonu.weebly.com/uploads/1/3/4/7/134719403/guvugujojepome.pdfIn PDF document text
    • https://pexafibilo.weebly.com/uploads/1/3/4/4/134484824/bc6ce3686a91194.pdfIn PDF document text
    • https://gezixipa.weebly.com/uploads/1/3/4/5/134503119/5ec07f86.pdfIn PDF document text
    • https://xujixokotejol.weebly.com/uploads/1/3/5/3/135308581/nabanabasinedimirit.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495975/normal_6051fbc70c1e0.pdfIn PDF document text
    • https://puxonuge.weebly.com/uploads/1/3/1/3/131383548/zonesajujutab_zejir_patumepa.pdfIn PDF document text
    • https://nekitunanozot.weebly.com/uploads/1/3/5/3/135346928/webofevepafepolopasa.pdfIn PDF document text
    • https://nerisowale.weebly.com/uploads/1/3/1/4/131412290/e7b29be22d53c.pdfIn PDF document text
    • https://welabelodaset.weebly.com/uploads/1/3/5/3/135399274/253bcd0.pdfIn PDF document text
    • https://zomanuvid.weebly.com/uploads/1/3/4/4/134477829/4154873.pdfIn PDF document text
    • https://tapojanez.weebly.com/uploads/1/3/1/3/131398133/0d3f5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475741/normal_6004dae747ab5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420430/normal_6028b13ee7865.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://taxexuwej.pbworks.com/w/file/fetch/144431295/bineriwawog.pdfIn PDF document text
    • http://wejojixi.pbworks.com/w/file/fetch/144424014/dedutuxinigudukalopezuze.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1cfcbf9-80ba-48d4-9327-b0a6c078d7ec/fadorujozimumad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0ef26dab-e836-4adf-9a75-9bbe4e359f8f/sududizikotuputewesurobi.pdfIn PDF document text
    • http://sewafebi.pbworks.com/w/file/fetch/144426114/43051191102.pdfIn PDF document text
    • http://xojifot.pbworks.com/w/file/fetch/144426468/83050369001.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/64dee461-d3d1-4a39-95a5-27c564ac0f4b/manunawazabugezotiropul.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a6a7a82-528c-4c5c-82db-5b13b8ee0a2d/75492279946.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_off0000e8f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8F6 5328 bytes
SHA-256: 0ebeb592946dda1db9d39896dc5a898d803982440e1117d118dfff851ad653f4
font_01_sfnt_off0000faf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF9 10652 bytes
SHA-256: 4c3f3a088b769d3be8d13ee564cb99613f26a60b7a9c9968d4fad4e2f81e4224