Malicious PDF — malware analysis report

Static analysis result for SHA-256 99cfd543f994e76a…

MALICIOUS

PDF

88.0 KB Created: 2021-02-23 04:31:01 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 644f9edcdef1ace88298eb7b7805ce9e SHA-1: ae237ea4021378db7ca3db181673966ea5702bc0 SHA-256: 99cfd543f994e76a7b0fd7efa7b81964e33f0cbdd09fbef7cb98340989730b5b
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains multiple external URIs, including one that appears to be a link farm on disposable hosting, suggesting a phishing or malware distribution lure. While no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attack pattern involving redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 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://seumenha.ru/strik?utm_term=rick+and+morty+comic+book+set
    • http://forecast.bet/articles_of_association_template_estoniaha9d8.pdf
    • http://cparta.moscow/grandia_guidejhijw.pdf
    • http://pidedex.22web.org/85552082016.pdf
    • https://komamezumef.weebly.com/uploads/1/3/1/3/131398541/jinodobul.pdf
    • https://lexizade.weebly.com/uploads/1/3/4/3/134368494/nalizat.pdf
    • https://static.s123-cdn-static.com/uploads/4485821/normal_5fcd72e39d401.pdf
    • https://nikatomorufaxeg.weebly.com/uploads/1/3/1/4/131437252/jolajimuda.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://nokolul.epizy.com/10999122983.pdf
    • https://s3.amazonaws.com/viromibukoleliw/30427636277.pdf
    • http://bivujugekoxuso.rf.gd/87523932288.pdf
    • http://zuxebalu.rf.gd/85865425887.pdf
    • https://s3.amazonaws.com/pidufozu/lelakobigexu.pdf
    • https://s3.amazonaws.com/musoxifuvitalo/fixitagelaxumidap.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001193f.bin
38717dfa42e858e491899db8172f631fd57028c4724d58a91522eb953e75a993
pdf-font-stream PDF embedded font (sfnt) at offset 0x1193F 5364 bytes
font_01_sfnt_off00012b75.bin
a2f6c73605d784cbed5496bf34be0d683e17e9180de423c8a3b99d0708276ee7
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B75 11772 bytes