Malicious PDF — malware analysis report

Static analysis result for SHA-256 fee01ea3b7c90133…

MALICIOUS

PDF

73.9 KB Created: 2021-02-16 09:21:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e90e35efc6a377d0f5f900adf4032d38 SHA-1: 0d30592452f9b72a12930b9033b160d78824eb0c SHA-256: fee01ea3b7c9013334f30287de3c14133f3ef1867bd1df789c1782cd7b64bb79
156 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many pointing to S3 buckets, which is characteristic of SEO link farm abuse. One of the primary external links, https://jacksth.ru/strik, is suspicious and likely leads to a malicious site. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan. The presence of embedded URLs and the overall structure suggest an attempt to redirect users to potentially harmful content.

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jacksth.ru/strik?utm_term=why+atp+is+a+high+energy+structure
    • http://lg-copyrightforms.com/effective_speech_and_oral_communicationr7sm8.pdf
    • https://xuvakaxatal.weebly.com/uploads/1/3/1/0/131070170/manubijibifonex.pdf
    • http://flipping-car.online/stickman_warriors_shadow_fight_mod_apkefrlw.pdf
    • http://detonic-romania.website/trap_drum_pads_guru_apkpureahs2s.pdf
    • http://lishop.site/nozekivanarinadql7b.pdf
    • http://damvglaz2.xyz/anatomy_of_the_constitution_preamble_activity_answersm27u4.pdf
    • http://brettlockhart.com/datojepl7hpa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/kelageketisefuv/fuwagob.pdf
    • https://s3.amazonaws.com/bezutu/abacus_maths_year_5_answers.pdf
    • https://s3.amazonaws.com/satulibaren/wopinurugepomuvafaxovi.pdf
    • https://s3.amazonaws.com/vesubodufisi/34083258565.pdf
    • https://s3.amazonaws.com/widiku/98357862963.pdf
    • https://s3.amazonaws.com/kobivimelelo/82486379074.pdf
    • https://s3.amazonaws.com/numegubowalonan/eicar_test_files.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_off0000e326.bin
a2e577f853ac19bf575fd12373297c20ee74b69baa4484a0c2147d7c8e1d7344
pdf-font-stream PDF embedded font (sfnt) at offset 0xE326 5280 bytes
font_01_sfnt_off0000f52f.bin
a5871c2b80203e16ec4eb578fd58cdf99f91b021e549e1e9c3bcf0149a304831
pdf-font-stream PDF embedded font (sfnt) at offset 0xF52F 11020 bytes