Malicious PDF — malware analysis report

Static analysis result for SHA-256 870f418b40e6ec26…

MALICIOUS

PDF

86.4 KB Created: 2021-06-02 22:49:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: fbb4f7e3e450147e699cf616b39beec8 SHA-1: 74d2fcd05867366ec86d2471200ce0186bfab54a SHA-256: 870f418b40e6ec26d901d2cdd42a0f4441691d052f2b94607803a5fe480c6274
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded URLs and the document's deceptive presentation as an assignment form support a spearphishing attachment attack pattern.

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://drafthe.ru/pbw?utm_term=tnou+assignment+submission+form+pdf PDF link annotation
    • https://jasuxazej.weebly.com/uploads/1/3/4/8/134875243/1fa94f83cccea37.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424341/normal_5fedd2367006a.pdfIn PDF document text
    • https://ponuxarazuzega.weebly.com/uploads/1/3/5/3/135328107/kajodogux.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369318/normal_5fd9d961a83c7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497646/normal_605aec114e834.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448540/normal_60430f1564c00.pdfIn PDF document text
    • https://zaloposigino.weebly.com/uploads/1/3/0/7/130739621/68efb160b1c4a.pdfIn PDF document text
    • https://didunomupipopad.weebly.com/uploads/1/3/1/4/131438203/lifekabovoxu.pdfIn PDF document text
    • https://rogofimek.weebly.com/uploads/1/3/3/9/133997266/3810475.pdfIn PDF document text
    • https://zulaxavon.weebly.com/uploads/1/3/2/6/132695675/xomozevigazol_garupapebubexe_nolozeturag.pdfIn PDF document text
    • https://dodivivedi.weebly.com/uploads/1/3/3/9/133997878/9558e84.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496810/normal_5ffd44a324b14.pdfIn PDF document text
    • https://fugiweritukasuj.weebly.com/uploads/1/3/4/6/134682589/81667e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475874/normal_5fde2ea6ce745.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366007/normal_606d425b376dc.pdfIn PDF document text
    • https://jasitonil.weebly.com/uploads/1/3/4/0/134096785/tevezanirokun_pimav.pdfIn PDF document text
    • https://dibegojiziwezed.weebly.com/uploads/1/3/0/7/130739363/gijanodum.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458618/normal_6037c677bf92d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450719/normal_602c82074772e.pdfIn PDF document text
    • https://jijidiwudop.weebly.com/uploads/1/3/4/4/134481930/4935073.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/84defc86-223b-4255-b313-a926c566339b/carenado_s550_citation_ii_tutorial.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/736ae493-cdc8-4b85-98e6-68d2d215cf62/varosoxigadoxig.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_off0001108f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108F 5416 bytes
SHA-256: d8e817c82b7c02b5a0ed53967af6fec14b4d77ba9719b17c9f7c16822e4eee8f
font_01_sfnt_off000122da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122DA 11720 bytes
SHA-256: 5ca4c3ad83ef44619a20d25cc8d304f3ce5e47b22efdc9c7b8b3353553a5600d