Malicious PDF — malware analysis report

Static analysis result for SHA-256 d76d57ae5949d172…

MALICIOUS

PDF

76.9 KB Created: 2021-02-19 21:29:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 96169b62cd6da65b3f2068c25d327c03 SHA-1: c1c280692b2fa8421095cbc74f49721fbdb0a66d SHA-256: d76d57ae5949d17217fc1e9096526db02dff47da58d81ef6dd36031c5f797800
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, with the primary URL being `https://bologen.ru/strik?utm_term=cortisone+shot+in+the+knee`. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan. The presence of numerous external links suggests an attempt to redirect users to potentially malicious sites for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bologen.ru/strik?utm_term=cortisone+shot+in+the+knee
    • http://prostotit.site/significant_digits_addition_and_subtraction_worksheet559wj.pdf
    • https://cdn.sqhk.co/maxegugej/PpNgdIn/access_gmail_contacts_in_outlook.pdf
    • https://cdn.sqhk.co/titabofasika/iZbNsie/46395553126.pdf
    • https://cdn.sqhk.co/vefusujix/B5OiggI/proton_bus_simulator_2020_download.pdf
    • https://cdn.sqhk.co/muvotugi/jdhgO21/28987452912.pdf
    • https://cdn.sqhk.co/dubikewe/ZAgeJOF/vugupolo.pdf
    • http://opros.xyz/ladexopaloxesopedipo3ch65.pdf
    • https://totidulabi.weebly.com/uploads/1/3/1/6/131606487/nunabirijobar-tegozirufed-vomefewoso.pdf
    • https://sefujokugitexas.weebly.com/uploads/1/3/1/4/131408298/lasofo.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/xujitezu/71009761979.pdf
    • http://luremugaxufarup.epizy.com/paxilumitabobupowogal.pdf
    • https://s3.amazonaws.com/vuliwisuwig/vixikivelejolesimara.pdf
    • http://novoboninixeme.epizy.com/81003778397.pdf
    • http://malenezi.epizy.com/hp_laserjet_p2015dn_error_codes.pdf
    • https://s3.amazonaws.com/memobofilenabon/plural_nouns_with_es_and_ies_worksheets.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_off0000f39f.bin
375ad6edfe4a8b4216638bfe2ff9f5caaaa0fbd31a11c5c4ede64d17c379e010
pdf-font-stream PDF embedded font (sfnt) at offset 0xF39F 4500 bytes
font_01_sfnt_off000102df.bin
a51bc2b3461c69b2f68afdba93ccf6135cb0cc6b72ba469bd00fc42e4e101f0c
pdf-font-stream PDF embedded font (sfnt) at offset 0x102DF 10688 bytes