Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4dfa9328cca87ed…

MALICIOUS

PDF

76.2 KB Created: 2021-03-10 08:35:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: c733070bd4337b2bf32ec5900fc2836a SHA-1: 2781df2e26971ed08f0626d0fe5dcff3f68c1f67 SHA-256: a4dfa9328cca87edcd0528eefa23f1a4d3c7730bb517bd6670aaec0ae879c23f
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 hosting services, indicating a link farm or SEO spam campaign. The primary URL, https://baarspo.ru/aws, is likely part of a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly support the malicious nature of this document.

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://baarspo.ru/aws?utm_term=detailed+summary+of+the+husband%2527s+secret PDF link annotation
    • https://likerediweraj.weebly.com/uploads/1/3/4/6/134691167/wawalinipudafoxiko.pdfIn PDF document text
    • https://xavamukunakupa.weebly.com/uploads/1/3/1/4/131437969/fetivefok-nubigipu-guxabalufatuwa-xijuruwemuloxa.pdfIn PDF document text
    • https://subogepaweb.weebly.com/uploads/1/3/2/3/132302814/1254345.pdfIn PDF document text
    • https://lajogaful.weebly.com/uploads/1/3/4/4/134481829/wazovefarubeg-bilefix-lasozajejowezom-wivebu.pdfIn PDF document text
    • https://bovabesizepin.weebly.com/uploads/1/3/1/3/131383515/wozifobevilabixuna.pdfIn PDF document text
    • https://cdn.sqhk.co/ragejeli/GxyDVha/durujivimomowogulubipor.pdfIn PDF document text
    • https://cdn.sqhk.co/mujawiru/hfghehe/yellow_cab_azuela_cove_menu.pdfIn PDF document text
    • https://cdn.sqhk.co/tuwesedujila/lYOihgi/fepujikililegikisunimijir.pdfIn PDF document text
    • https://jabasamivesapev.weebly.com/uploads/1/3/4/0/134041177/ea2cd.pdfIn PDF document text
    • https://cdn.sqhk.co/musutalivun/gegOsjb/lufuzakunobewusetafisi.pdfIn PDF document text
    • https://namekabesomi.weebly.com/uploads/1/3/4/6/134668803/letumo-wulefosarebot-tifunoxubuf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3bcdeb60-9876-4d14-bc0a-1dd1632c647c.filesusr.com/ugd/16a96a_b729061f1ad1458aa370e8966f8fb2b0.pdf?index=trueIn PDF document text
    • http://diwuvugu.epizy.com/pubavuwep.pdfIn PDF document text
    • http://kuxoxulid.epizy.com/50971468751.pdfIn PDF document text
    • http://dulidezupo.rf.gd/67741000253.pdfIn PDF document text
    • https://b01ec662-dec5-4f54-b977-8708717d6054.filesusr.com/ugd/07e02c_320b33c6bd98459bba7728c2e9d51a9a.pdf?index=trueIn PDF document text
    • http://vonuvaxi.epizy.com/44911265724.pdfIn PDF document text
    • https://e8e87dc5-637d-47ba-9de6-e7d98d123d78.filesusr.com/ugd/a69a03_7ffa8f96bdb64cbfa1996454949ac7c3.pdf?index=trueIn PDF document text
    • https://44eeb0f0-4dc9-4d8b-b3fd-cc7ace98e90e.filesusr.com/ugd/a083a1_5c9ad5bcefdf486c98502cd907eb287c.pdf?index=trueIn PDF document text
    • https://02796127-04ec-4c85-b270-c6f7310ebb18.filesusr.com/ugd/ce0e6d_a52579b7daac4bcfb219deddaf9d4086.pdf?index=trueIn PDF document text
    • http://rexuworov.epizy.com/covid-19_news_los_angeles_ca.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_off0000ee54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE54 5536 bytes
SHA-256: 19c82075f69d41aa96d56aafbc12038a4511a28ac4412f95c19864d96eaaeb5c
font_01_sfnt_off00010113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10113 9952 bytes
SHA-256: da2816ec85c730db58ac7bd305a1d2d57fd64ddcd80eb622ab8528534c50e873