Malicious PDF — malware analysis report

Static analysis result for SHA-256 234cc5937e55caba…

MALICIOUS

PDF

90.5 KB Created: 2021-02-17 10:53:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 26b6c62f9ee25dcf28ba9e53529bb6c3 SHA-1: ba5b6f6195b50fcdd297a1f3fd373279101ed774 SHA-256: 234cc5937e55cabafabc491ab85f6dac9ea3f4686548260946010a65f803aa88
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

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://jottigo.ru/123?utm_term=diagrama+de+fases+del+agua+explicacion PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366358/normal_6015a541823e9.pdfIn PDF document text
    • http://callup.today/variante_bac_chimie_anorganicak9woj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449965/normal_602c5ba7bfc25.pdfIn PDF document text
    • https://cdn.sqhk.co/zevukodixu/eic3z2o/wabepeware.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445735/normal_5fe20cbd0f36b.pdfIn PDF document text
    • https://cdn.sqhk.co/duromivap/idibijc/ally_zack_smash_bros.pdfIn PDF document text
    • https://larezonisu.weebly.com/uploads/1/3/0/7/130738889/4201035.pdfIn PDF document text
    • https://cdn.sqhk.co/midipijikami/L8Tgehh/44805436807.pdfIn PDF document text
    • http://hangookoil.ru/codigo_penal_puerto_rico_adulterioisk2a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370989/normal_5fcd76d9634fb.pdfIn PDF document text
    • https://cdn.sqhk.co/nupozifulija/ia93GvU/1539812538.pdfIn PDF document text
    • https://cdn.sqhk.co/zepipawetopi/sjjidxB/pitzmaker_mod_apk_unlimited_money.pdfIn PDF document text
    • https://nugobobunebiset.weebly.com/uploads/1/3/5/3/135303429/mezefokeleto-kozewejezukepo-koxafifi-molodawawujuw.pdfIn PDF document text
    • https://tusezewepoxir.weebly.com/uploads/1/3/4/3/134339989/bef45.pdfIn PDF document text
    • https://cdn.sqhk.co/lifudidu/cnMZJjh/new_ringtone_2020_punjabi.pdfIn PDF document text
    • http://lunesygets.xyz/fifawewamajolumabo6b1cx.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490376/normal_6016a9dbd92b5.pdfIn PDF document text
    • https://cdn.sqhk.co/bupedamarib/hbgxjEO/battle_strikers_website.pdfIn PDF document text
    • https://cdn.sqhk.co/vimewiki/jc09hjY/2nd_grade_writing_activity_worksheets.pdfIn PDF document text
    • http://sfr-espace.best/black_friday_sales_down_2020zs81x.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000108da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DA 5540 bytes
SHA-256: 92435fd8f666d09373c27e79528f100cab94052c71423a1cabc3ab00fe6b18fa
font_01_sfnt_off00011bae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BAE 12852 bytes
SHA-256: fec70456f4aa0c9ab8f4dd8983668ad6e71422bc69e95aaf72a28c0f861038ad
font_02_sfnt_off0001458f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1458F 16080 bytes
SHA-256: 3d50f22d3ae6d9a4461c814f81554cc573a3512c555c2f223aedeeaca19cd658